WO2023184870A1

WO2023184870A1 - Thermal management method and apparatus for power battery, and electronic device and storage medium

Info

Publication number: WO2023184870A1
Application number: PCT/CN2022/117355
Authority: WO
Inventors: 王欣欣; 王明强; 马建生; 张虎; 张洪雷; 张旭
Original assignee: 合众新能源汽车股份有限公司
Priority date: 2022-04-01
Filing date: 2022-09-06
Publication date: 2023-10-05
Also published as: CN114792857B; CN114792857A

Abstract

Embodiments of the present application provide a thermal management method and apparatus for a power battery. The method comprises: acquiring a terminal voltage value, a current value, and an external temperature value of the power battery in a preset state-of-charge change interval; obtaining an internal temperature value of the power battery in the state-of-charge change interval according to the terminal voltage value, the current value, the external temperature value, and battery parameters of the power battery; generating an external temperature rise rate and an internal temperature rise rate of the power battery according to the external temperature value, the internal temperature value, and a time period of the state-of-charge change interval; and comparing the external temperature rise rate with the internal temperature rise rate, and selecting the external temperature value or the internal temperature value according to a comparison result to perform thermal management on the power battery. According to the embodiments of the present application, a temperature threshold value is prevented from being set according to experience, and the thermal management can be accurately performed on the power battery.

Description

Thermal management methods, devices, electronic equipment and storage media for power batteries

This application requires the priority of the Chinese patent application submitted to the China Patent Office on April 1, 2022, with the application number 202210339662.6 and the invention title "Thermal management method, device, electronic equipment and storage medium for power batteries", and its entire content incorporated herein by reference.

Technical field

The present application relates to the field of automotive technology, and in particular to a thermal management method, device, electronic equipment and computer-readable storage medium for a power battery.

Background technique

With the promotion and application of new energy vehicles, while electric vehicles have become important means of transportation, they are also facing technical challenges such as charging speed, cycle life, and battery thermal management. In order to achieve the best performance and life of the power battery, it is necessary to control the temperature rise rate and temperature difference of the power battery through low-temperature heating, high-temperature cooling, uniform temperature management and other measures to keep it operating within a suitable temperature range. The temperature control methods mentioned above are all uniformly reflected in the thermal management strategy.

At present, most electric vehicles adopt a relatively simple thermal management strategy, which only uses experience-based temperature thresholds to control the heating and cooling of power batteries. That is, when the battery temperature is low/above a certain temperature value, heating/cooling is turned on, and when the battery temperature is high, the heating/cooling is turned on. / When the temperature is lower than a certain value, cooling/heating is turned on. This thermal management strategy, which is based on the battery temperature collected by the temperature sensor as the main parameter, is highly dependent on the analog signal and digital signal acquisition chip, sensor accuracy and layout. The temperature measured by the sensor is the battery surface temperature, and the actual temperature inside the battery is ignored, making it impossible to accurately manage the thermal management of the power battery.

Contents of the invention

In view of the above problems, embodiments of the present application are proposed to provide a thermal management method, device, electronic device and computer-readable storage medium for a power battery that overcomes the above problems or at least partially solves the above problems.

In order to solve the above problem, according to the first aspect of the embodiment of the present application, a thermal management method for a power battery is disclosed. The method includes: obtaining the terminal voltage value and current value of the power battery in a preset state-of-charge change interval. and external temperature value; obtain the internal temperature value of the power battery in the state of charge change interval according to the terminal voltage value, the current value, the external temperature value and the battery parameters of the power battery; according to the The external temperature value and the time period of the state of charge change interval generate the external temperature rise rate of the power battery, and generate the internal temperature rise rate of the power battery based on the internal temperature value and the time period; The external temperature rise rate and the internal temperature rise rate are compared to obtain a comparison result, and the external temperature value or the internal temperature value is selected according to the comparison result to perform thermal management on the power battery.

Optionally, obtaining the internal temperature value of the power battery in the state-of-charge change interval based on the terminal voltage value, the current value, the external temperature value and battery parameters of the power battery includes: : Calculate the heat generation rate of the power battery according to the terminal voltage value, the current value, the external temperature value, the open circuit voltage value in the battery parameters, the temperature coefficient, and the battery volume; according to the heat generation rate , the average density, average heat capacity, average thermal conductivity, temperature rise rate parameters among the battery parameters and the time period are used to calculate the internal temperature value.

Optionally, calculating the heat generation rate of the power battery based on the terminal voltage value, the current value, the external temperature value, the open circuit voltage value in the battery parameters, the temperature coefficient, and the battery volume includes: :according to

Calculate the heat generation rate; where, q represents the heat generation rate, I represents the current value, V _OC represents the open circuit voltage value, V represents the terminal voltage value, and T represents the external temperature value,

represents the temperature coefficient, and V _bat represents the battery volume.

Optionally, calculating the internal temperature value based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters and the time period among the battery parameters includes:

Calculate the internal temperature value; where q represents the heat generation rate, ρ represents the average density, C _p represents the average heat capacity,

represents the temperature rise rate parameter, T _in represents the internal temperature value, t represents the time period, λ represents the average thermal conductivity, and ΔT represents the difference between the internal temperature value and the external temperature value.

Optionally, selecting the internal temperature value according to the comparison result to perform thermal management on the power battery includes: when the comparison result indicates that the internal temperature rise rate is greater than or equal to the external temperature rise rate , select the lowest internal temperature value from the internal temperature values to perform thermal management on the power battery.

Optionally, selecting the external temperature value according to the comparison result to perform thermal management on the power battery includes: when the comparison result indicates that the internal temperature rise rate is less than the external temperature rise rate, from Select the lowest external temperature value among the external temperature values to perform thermal management on the power battery.

According to a second aspect of the embodiment of the present application, a thermal management device for a power battery is also disclosed. The device includes: a battery measurement module, used to obtain the terminal voltage value of the power battery in a preset state-of-charge change interval, Current value and external temperature value; internal temperature acquisition module, used to obtain the state of charge of the power battery according to the terminal voltage value, the current value, the external temperature value and the battery parameters of the power battery. The internal temperature value of the change interval; a temperature rise acquisition module, configured to generate the external temperature rise rate of the power battery according to the external temperature value and the time period of the state of charge change interval, and generate the external temperature rise rate of the power battery according to the internal temperature value and the time period of the state-of-charge change interval. The time period generates the internal temperature rise rate of the power battery; a thermal management module is used to compare the external temperature rise rate and the internal temperature rise rate to obtain a comparison result, and select the external temperature rise rate according to the comparison result. The temperature value or the internal temperature value performs thermal management on the power battery.

Optionally, the internal temperature acquisition module includes: a heat generation rate calculation module, configured to calculate the internal temperature according to the terminal voltage value, the current value, the external temperature value, the open circuit voltage value, and temperature among the battery parameters. coefficient and battery volume to calculate the heat generation rate of the power battery; an internal temperature calculation module is used to calculate the heat generation rate, average density, average heat capacity, average thermal conductivity, and temperature rise rate parameters among the battery parameters. and the time period to calculate the internal temperature value.

Optionally, the heat generation rate calculation module is used to calculate the

Optionally, the internal temperature calculation module is used to calculate the

Optionally, the thermal management module is configured to select the lowest internal temperature value from the internal temperature values to match the internal temperature rise rate when the comparison result indicates that the internal temperature rise rate is greater than or equal to the external temperature rise rate. Power battery thermal management.

Optionally, the thermal management module is configured to select the lowest external temperature value from the external temperature values for the power battery when the comparison result indicates that the internal temperature rise rate is less than the external temperature rise rate. Perform thermal management.

According to a third aspect of the embodiment of the present application, an electronic device is also disclosed, including a memory, a processor, and a computer program stored on the memory and executable on the processor. The processor executes the computer program. When realizing the thermal management method of a power battery described in the first aspect.

According to a fourth aspect of the embodiments of the present application, a computer-readable storage medium is also disclosed, on which a computer program is stored. When the program is executed by a processor, the thermal management method of a power battery described in the first aspect is implemented. .

According to a fifth aspect of the embodiments of the present application, a computer program product is provided, including computer readable code. When the computer readable code is run on an electronic device, it causes the electronic device to execute the method described in the first aspect. A thermal management method for power batteries.

Compared with the existing technology, the technical solutions provided by the embodiments of the present application have the following advantages:

The embodiment of the present application provides a thermal management solution for a power battery, which obtains the terminal voltage value, current value and external temperature value of the power battery in a preset state-of-charge change interval, and then uses the terminal voltage value, current value and external temperature value to value and the battery parameters of the power battery to obtain the internal temperature value of the power battery in the state of charge change interval. It should be noted that the obtained internal temperature value may be an internal temperature value range including the lowest internal temperature value and the highest internal temperature value. Then, the external temperature rise rate in the state of charge change interval is compared with the internal temperature rise rate to obtain a comparison result. Finally, based on the comparison result, the internal temperature value or the external temperature value is selected to perform thermal management of the power battery.

The embodiment of the present application obtains the internal temperature value of the power battery based on the measured terminal voltage value, current value and external temperature value of the power battery, as well as the battery parameters of the power battery itself. Compare the external temperature rise rate and the internal temperature rise rate, and select the external temperature value as the temperature threshold or the internal temperature value as the temperature threshold based on the comparison result, avoiding the need to set the temperature threshold based on experience, and the power battery can be accurately thermally managed.

The above description is only an overview of the technical solutions of the present application. In order to have a clearer understanding of the technical means of the present application, they can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable. , the specific implementation methods of the present application are specifically listed below.

Description of drawings

In order to more clearly explain the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description These are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a step flow chart of a thermal management method for a power battery according to an embodiment of the present application;

Figure 2 is a schematic flow chart of a thermal management strategy optimization solution based on internal temperature estimation according to an embodiment of the present application;

Figure 3 is a structural block diagram of a thermal management device for a power battery according to an embodiment of the present application;

Figure 4 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Specific embodiments

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments These are part of the embodiments of this application, but not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

Referring to FIG. 1 , a flow chart of steps of a thermal management method for a power battery according to an embodiment of the present application is shown. The thermal management method of power batteries can be applied to new energy vehicles equipped with power batteries. The thermal management method of the power battery may specifically include the following steps:

Step 101: Obtain the terminal voltage value, current value and external temperature value of the power battery in a preset state-of-charge change interval.

In the embodiment of the present application, relevant data that combines working condition characteristics and environmental parameters are identified based on the actual driving conditions of the car. Usually, complex driving conditions are reflected in changes in the current value and state of charge (SOC) of the power battery. In practical applications, the state of charge of the power battery is maintained between the depleted state and the fully charged state. Therefore, the embodiment of the present application can set a state of charge change interval. For example, the state of charge change interval is 20% to 90%. When the state of charge of the power battery is in the state of charge change interval, measure the terminal voltage value, current value and external temperature value of the power battery.

It should be noted that the measured terminal voltage value, current value and external temperature value are not all constant values. During the actual measurement process, the terminal voltage value, current value and external temperature value can all be within a numerical range. That is to say, multiple terminal voltage values, current values and external temperature values can be measured.

Step 102: Obtain the internal temperature value of the power battery in the state of charge change interval according to the terminal voltage value, current value, external temperature value and battery parameters of the power battery.

In embodiments of the present application, based on the heat generation characteristics of the power battery, an estimation model of the internal temperature value can be constructed, and then the estimation model can be used to estimate the actual temperature of the power battery during vehicle driving. The above estimation model of the internal temperature value involves the terminal voltage value, current value, external temperature value and battery parameters of the power battery. Among them, the battery parameters of the power battery can be obtained from the power battery supplier, and the battery parameters can be understood as the attributes of the power battery.

Step 103: Generate the external temperature rise rate of the power battery based on the external temperature value and the time period of the state of charge change interval, and generate the internal temperature rise rate of the power battery based on the internal temperature value and time period.

In the embodiment of the present application, the external temperature rise rate and the internal temperature rise rate of the power battery in the state of charge change interval are calculated respectively. Among them, the external temperature rise rate is obtained from the external temperature value and the time period of the state of charge change interval. The internal temperature rise rate is obtained from the internal temperature value and the time period of the state of charge change interval.

Step 104: Compare the external temperature rise rate and the internal temperature rise rate to obtain a comparison result, and select an external temperature value or an internal temperature value according to the comparison result to perform thermal management on the power battery.

In the embodiment of the present application, after obtaining the external temperature rise rate and the internal temperature rise rate, the external temperature rise rate and the internal temperature rise rate are compared to obtain a comparison result. The external temperature value is selected as the temperature threshold based on the comparison result, or the internal temperature value is selected as the temperature threshold based on the comparison result. Furthermore, the selected temperature threshold is used to perform thermal management on the power battery.

In a preferred embodiment of the present application, an implementation method for obtaining the internal temperature value of the power battery in the state of charge change interval based on the terminal voltage value, current value, external temperature value and battery parameters of the power battery is to: The voltage value, current value, external temperature value, open circuit voltage value in battery parameters, temperature coefficient, and battery volume are used to calculate the heat generation rate of the power battery. The internal temperature value is then calculated based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters and the time period of the state of charge change interval in the battery parameters.

In practical applications, when calculating the heat generation rate of a power battery based on the terminal voltage value, current value, external temperature value, open circuit voltage value in battery parameters, temperature coefficient, and battery volume, the heat generation rate can be calculated according to the following formula:

Where, q represents the heat generation rate, I represents the current value, V _OC represents the open circuit voltage value, V represents the terminal voltage value, and T represents the external temperature value,

In practical applications, when calculating the internal temperature value based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters and the time period of the state of charge change interval in the battery parameters, it can be calculated according to the following formula Internal temperature value:

Where, q represents the heat generation rate, ρ represents the average density, C _p represents the average heat capacity,

In a preferred embodiment of the present application, an implementation method of selecting an internal temperature value for thermal management of a power battery based on a comparison result is: when the comparison result indicates that the internal temperature rise rate is greater than or equal to the external temperature rise rate, Select the lowest internal temperature value among the temperature values to perform thermal management of the power battery. That is to say, when the internal temperature rise rate is greater than or equal to the external temperature rise rate, in order to avoid overheating inside the power battery, the lowest internal temperature value is selected from the internal temperature values as the internal temperature threshold. Use internal temperature values and internal temperature thresholds for thermal management of power batteries. For example, the lowest internal temperature value is used as the threshold for turning on and off the heating state of the power battery while charging.

In a preferred embodiment of the present application, an implementation method of selecting an external temperature value for thermal management of the power battery based on the comparison result is: when the comparison result indicates that the internal temperature rise rate is less than the external temperature rise rate, selecting the external temperature value from the external temperature value. Select the lowest external temperature value to perform thermal management on the power battery. That is to say, when the internal temperature rise rate is smaller than the external temperature rise rate, in order to reduce the extension of charging time caused by insufficient average temperature of the power battery, the lowest external temperature value is selected from the external temperature values as the external temperature threshold. The external temperature value and external temperature threshold are used for thermal management of the power battery. For example, the lowest external temperature value is used as the threshold for turning on and off the heating state of the power battery while charging.

Based on the above description of the embodiment of a thermal management method for a power battery, a thermal management strategy optimization solution based on internal temperature estimation is introduced below. Based on this thermal management strategy optimization scheme, the power battery of new energy vehicles can be thermally managed.

Referring to FIG. 2 , a schematic flow chart of a thermal management strategy optimization solution based on internal temperature estimation is shown.

At present, the thermal management requirements of power batteries for new energy vehicles usually include measures such as low-temperature heating, high-temperature cooling, and uniform temperature management. In order to implement the above measures, data related to working condition characteristics and environmental parameters can be identified based on the actual driving conditions of new energy vehicles. For example, the actual current (current value) and SOC can be identified. In addition, the terminal voltage value and external temperature value of the power battery can also be measured. Then, the internal temperature value of the power battery in the SOC change range is estimated based on the current value, SOC, terminal voltage value, battery parameters of the power battery, and internal temperature estimation model. Based on the internal temperature value in the SOC change interval, the internal temperature rise rate and internal temperature difference of the power battery in the SOC change interval can be calculated. Based on the external temperature value in the SOC change interval, the external temperature rise rate and external temperature difference of the power battery in the SOC change interval can be calculated. Next, the external temperature rise rate is compared with the internal temperature rise rate. If the external temperature rise rate is greater than the internal temperature rise rate, the external minimum temperature is used as the conversion threshold (external temperature threshold) of the power battery thermal management state. If the external temperature rise rate is less than or equal to the internal temperature rise rate, the internal minimum temperature is used as the conversion threshold of the power battery thermal management state (internal temperature threshold). Finally, the thermal management strategy of the power battery is executed based on the selected external temperature threshold or internal temperature threshold.

According to the heat generation characteristics of the power battery, there is a certain difference between the battery surface temperature measured based on the temperature sensor and the internal temperature of the battery. If corresponding thermal management measures are only based on the external temperature value, it will lead to excessive temperature difference and heat loss in the power battery pack. The problem of lagging management results. The embodiment of the present application estimates the internal temperature value of the power battery based on the actual driving conditions of the vehicle, corrects the delay and accuracy error of the external temperature value measured by the temperature sensor, and achieves precise thermal management of the power battery.

It should be noted that for the sake of simple description, the method embodiments are expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of the present application are not limited by the described action sequence, because According to the embodiments of the present application, certain steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily necessary for the embodiments of the present application.

Referring to Figure 3, there is shown a structural block diagram of a thermal management device for a power battery according to an embodiment of the present application. The thermal management device for a power battery can be applied to a new energy vehicle equipped with a power battery. The thermal management device for a power battery Specifically, it can include the following modules:

The battery measurement module 31 is used to obtain the terminal voltage value, current value and external temperature value of the power battery in the preset state-of-charge change interval;

The internal temperature acquisition module 32 is used to obtain the internal temperature value of the power battery in the state of charge change interval according to the terminal voltage value, the current value, the external temperature value and the battery parameters of the power battery. ;

The temperature rise acquisition module 33 is configured to generate the external temperature rise rate of the power battery based on the external temperature value and the time period of the state of charge change interval, and generate the external temperature rise rate based on the internal temperature value and the time period. Describe the internal temperature rise rate of the power battery;

Thermal management module 34 is used to compare the external temperature rise rate and the internal temperature rise rate to obtain a comparison result, and select the external temperature value or the internal temperature value to perform maintenance on the power battery according to the comparison result. Thermal management.

In a preferred embodiment of the present application, the internal temperature acquisition module 32 includes:

Heat generation rate calculation module, used to calculate the heat generation rate of the power battery based on the terminal voltage value, the current value, the external temperature value, the open circuit voltage value in the battery parameters, the temperature coefficient, and the battery volume. ;

An internal temperature calculation module, configured to calculate the internal temperature value based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters among the battery parameters, and the time period.

In a preferred embodiment of the present application, the heat generation rate calculation module is used to calculate the heat generation rate according to

Calculate the heat generation rate;

In a preferred embodiment of the present application, the internal temperature calculation module is used to calculate the internal temperature according to

Calculate said internal temperature value;

In a preferred embodiment of the present application, the thermal management module 34 is configured to obtain the internal temperature value from the internal temperature value when the comparison result indicates that the internal temperature rise rate is greater than or equal to the external temperature rise rate. Select the lowest internal temperature value for thermal management of the power battery.

In a preferred embodiment of the present application, the thermal management module 34 is configured to select the lowest external temperature value from the external temperature value when the comparison result indicates that the internal temperature rise rate is less than the external temperature rise rate. The external temperature value performs thermal management on the power battery.

The device embodiments described above are only illustrative. The modules described as separate components may or may not be physically separated. The components shown as modules may or may not be physical modules, that is, they may be located in One place, or it can be distributed across multiple networks. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Persons of ordinary skill in the art can understand and implement the method without any creative effort.

An embodiment of the present application also provides an electronic device, see Figure 4, including: a processor 401, a memory 402, and a computer program 4021 stored on the memory 402 and executable on the processor 401. The processing When the program 4021 is executed by the processor 401, the thermal management method of the power battery of the aforementioned embodiment is implemented.

Embodiments of the present application also provide a readable storage medium on which a computer program is stored. When the program is executed by a processor, the thermal management method of the power battery of the previous embodiment is implemented.

In yet another embodiment provided by this application, a computer program product containing instructions is also provided, which when run on a computer causes the computer to execute the thermal management method of the power battery in the above embodiment.

As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple. For relevant details, please refer to the partial description of the method embodiment.

It should be noted that all actions to obtain signals, information or data in the embodiments of this application are performed under the premise of complying with the corresponding data protection regulations and policies of the country where the location is located, and with authorization from the owner of the corresponding device.

Each embodiment in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other.

Those skilled in the art should understand that embodiments of the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, embodiments of the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, embodiments of the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

Embodiments of the present application are described with reference to flowcharts and/or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the present application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine such that the instructions are executed by the processor of the computer or other programmable data processing terminal device. Means are generated for implementing the functions specified in the process or processes of the flowchart diagrams and/or the block or blocks of the block diagrams.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing terminal equipment to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the The instruction means implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, so that a series of operating steps are performed on the computer or other programmable terminal equipment to produce computer-implemented processing, thereby causing the computer or other programmable terminal equipment to perform a computer-implemented process. The instructions executed on provide steps for implementing the functions specified in a process or processes of the flow diagrams and/or a block or blocks of the block diagrams.

Although preferred embodiments of the embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once the basic inventive concepts are understood. Therefore, the appended claims are intended to be construed to include the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

Finally, it should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or any such actual relationship or sequence between operations. Furthermore, the terms "comprises," "comprises," or any other variation thereof are intended to cover a non-exclusive inclusion such that a process, method, article, or end device that includes a list of elements includes not only those elements, but also elements not expressly listed or other elements inherent to such process, method, article or terminal equipment. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article or terminal device including the stated element.

The thermal management method and device of a power battery provided by the present application have been introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understanding. The method of this application and its core idea; at the same time, for those of ordinary skill in the field, there will be changes in the specific implementation and application scope based on the idea of this application. In summary, the contents of this specification should not understood as a limitation on this application.

Claims

A thermal management method for a power battery, wherein the method includes:

Obtain the terminal voltage value, current value and external temperature value of the power battery in the preset state of charge change interval;

Obtain the internal temperature value of the power battery in the state of charge change interval according to the terminal voltage value, the current value, the external temperature value and the battery parameters of the power battery;

The external temperature rise rate of the power battery is generated based on the external temperature value and the time period of the state of charge change interval, and the internal temperature rise rate of the power battery is generated based on the internal temperature value and the time period. ;

The external temperature rise rate and the internal temperature rise rate are compared to obtain a comparison result, and the external temperature value or the internal temperature value is selected according to the comparison result to perform thermal management on the power battery.
The method according to claim 1, wherein the state-of-charge change of the power battery is obtained based on the terminal voltage value, the current value, the external temperature value and battery parameters of the power battery. The internal temperature value of the interval, including:

Calculate the heat generation rate of the power battery according to the terminal voltage value, the current value, the external temperature value, the open circuit voltage value in the battery parameters, the temperature coefficient, and the battery volume;

The internal temperature value is calculated based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters among the battery parameters, and the time period.
The method according to claim 2, wherein the power is calculated based on the terminal voltage value, the current value, the external temperature value, an open circuit voltage value in the battery parameters, a temperature coefficient, and a battery volume. Battery heat generation rate, including:

according to
Calculate the heat generation rate;

Where, q represents the heat generation rate, I represents the current value, V OC represents the open circuit voltage value, V represents the terminal voltage value, and T represents the external temperature value,
represents the temperature coefficient, and V bat represents the battery volume.
The method according to claim 2, wherein the calculation is based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters and the time period among the battery parameters. Internal temperature values, including:

according to
Calculate said internal temperature value;

Where, q represents the heat generation rate, ρ represents the average density, C p represents the average heat capacity,
represents the temperature rise rate parameter, T in represents the internal temperature value, t represents the time period, λ represents the average thermal conductivity, and ΔT represents the difference between the internal temperature value and the external temperature value.
The method according to claim 1, wherein selecting the internal temperature value according to the comparison result to perform thermal management on the power battery includes:

When the comparison result indicates that the internal temperature rise rate is greater than or equal to the external temperature rise rate, select the lowest internal temperature value from the internal temperature values to perform thermal management on the power battery.
The method according to claim 1, wherein selecting the external temperature value according to the comparison result to perform thermal management on the power battery includes:

When the comparison result indicates that the internal temperature rise rate is less than the external temperature rise rate, select the lowest external temperature value from the external temperature values to perform thermal management on the power battery.
A thermal management device for a power battery, wherein the device includes:

The battery measurement module is used to obtain the terminal voltage value, current value and external temperature value of the power battery in the preset state-of-charge change interval;

An internal temperature acquisition module, configured to obtain the internal temperature value of the power battery in the state of charge change interval according to the terminal voltage value, the current value, the external temperature value and the battery parameters of the power battery;

A temperature rise acquisition module, configured to generate the external temperature rise rate of the power battery based on the external temperature value and the time period of the state of charge change interval, and generate the external temperature rise rate based on the internal temperature value and the time period. The internal temperature rise rate of the power battery;

The thermal management module is used to compare the external temperature rise rate and the internal temperature rise rate to obtain a comparison result, and select the external temperature value or the internal temperature value to heat the power battery according to the comparison result. manage.
The device according to claim 7, wherein the internal temperature acquisition module includes:

Heat generation rate calculation module, used to calculate the heat generation rate of the power battery based on the terminal voltage value, the current value, the external temperature value, the open circuit voltage value in the battery parameters, the temperature coefficient, and the battery volume. ;

An internal temperature calculation module, configured to calculate the internal temperature value based on the heat generation rate, average density, average heat capacity, average thermal conductivity, temperature rise rate parameters among the battery parameters, and the time period.
An electronic device, including a memory, a processor and a computer program stored on the memory and executable on the processor, wherein when the processor executes the computer program, any one of claims 1 to 6 is implemented The thermal management method of power battery.
A computer-readable storage medium on which a computer program is stored, wherein when the program is executed by a processor, the thermal management method of a power battery according to any one of claims 1 to 6 is implemented.
A computer program product, comprising computer readable code, when the computer readable code is run on an electronic device, causing the electronic device to perform thermal management of a power battery according to any one of claims 1 to 6 method.