Battery self-heating control method and device, medium, controller and program product

Abstract

The invention relates to a battery self-heating control method and device, a medium, a controller and a program product. The method comprises the following steps: acquiring a current excitation signal for self-heating and current state information of a battery; determining the current impedance of the battery according to the current excitation signal and the current state information; according to the current impedance, determining a target excitation signal for generating target self-heating power for the current impedance; and taking the target excitation signal as a new current excitation signal so as to carry out self-heating excitation adjustment on the battery. Through circulation control, the excitation signal used for self-heating is always close to the power requirement corresponding to the impedance of the battery, and it is guaranteed that the battery can maintain a good self-heating effect in the whole self-heating process.

Description

Technical Field

[0001] The present application relates to the technical field of battery management, and particularly to a battery self-heating control method, device, medium, controller and program product. Background Art

[0002] Heating the battery is mainly to improve its performance and safety, especially in low-temperature environments. Specifically, in low-temperature environments, the electrochemical reaction rate of lithium-ion batteries slows down, resulting in an increase in the internal resistance of the battery and a decrease in the discharge capacity. Heating the battery can increase its reaction rate, thereby improving the performance of the battery; at low temperatures, the electrolyte of the battery may crystallize, affecting the normal operation of the battery and even potentially causing safety problems. Heating can prevent the electrolyte from crystallizing and ensure the safe operation of the battery.

[0003] The self-heating of existing batteries generally includes various methods. For example, one method can utilize the current inside the battery to generate heat. This method can quickly increase the temperature of the battery, enabling it to reach the optimal working state in a short time and also avoiding dependence on external power sources. However, the control method of the existing method of using the battery to generate current is single, and the achieved self-heating effect is not good. Summary of the Invention

[0004] The embodiments of the present application provide a battery self-heating control method, device, medium, controller and program product, which can obtain the current excitation signal for self-heating the battery and the current state information of the battery in real time, thereby determining the current impedance of the battery, and further being able to determine the target self-heating power with a better self-heating effect for the current impedance and the target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as the new current excitation signal to adjust the excitation for self-heating the battery. Through cyclic control, the excitation signal for self-heating is always made to approach the power demand corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the entire self-heating process of the battery, so as to at least partially solve the above technical problems.

[0005] To achieve the above object, according to the first aspect of the present application, a battery self-heating control method is provided, including:

[0006] Obtain the current excitation signal for self-heating and the current state information of the battery;

[0007] Determine the current impedance of the battery according to the current excitation signal and the current state information;

[0008] Determine the target excitation signal for generating the target self-heating power for the current impedance according to the current impedance;

[0009] Use the target excitation signal as the new current excitation signal to adjust the excitation for self-heating the battery.

[0010] Optionally, the current state information includes current temperature state information and current state of charge information; determining the current impedance of the battery according to the current excitation signal and the current state information includes:

[0011] Determining the current frequency of the current excitation signal;

[0012] Determining the current impedance of the battery according to the current frequency, the current temperature state information, and the current state of charge information.

[0013] Optionally, determining the current impedance of the battery according to the current frequency, the current temperature state information, and the current state of charge information includes:

[0014] Matching corresponding sample frequency, sample temperature state information, and sample state of charge information in a target database constructed based on the electrochemical impedance spectrum of the battery according to the current frequency, the current temperature state information, and the current state of charge information;

[0015] Determining the sample impedance corresponding to the sample frequency, the sample temperature state information, and the sample state of charge information as the current impedance.

[0016] Optionally, determining a target excitation signal for generating a target self-heating power for the current impedance according to the current impedance includes:

[0017] Obtaining a plurality of candidate excitation signals;

[0018] Determining the candidate amplitude of each candidate excitation signal;

[0019] Determining the candidate self-heating power corresponding to each candidate amplitude according to the current impedance and each candidate amplitude;

[0020] Determining one of the candidate self-heating powers exceeding a preset power among the plurality of candidate self-heating powers as the target self-heating power and determining the corresponding candidate excitation signal as the target excitation signal.

[0021] Optionally, obtaining a plurality of candidate excitation signals includes:

[0022] Obtaining a plurality of initial excitation signals;

[0023] Determining the initial frequency of each initial excitation signal;

[0024] Determining the plurality of initial excitation signals with initial frequencies within a preset frequency range among the plurality of initial excitation signals as candidate excitation signals.

[0025] Optionally, determining the current impedance of the battery according to the current excitation signal and the current state information includes:

[0026] Decompose the current excitation signal into waveforms to obtain multiple current excitation waveforms;

[0027] According to each current excitation waveform and the current state information, determine the current sub-impedance corresponding to each current excitation waveform;

[0028] Obtain the current impedance based on multiple current sub-impedances.

[0029] Optionally, determine a target excitation signal for generating a target self-heating power for the current impedance, including:

[0030] Determine the target excitation signals corresponding to multiple target sub-excitation waveforms respectively used to generate target sub-self-heating powers for each current sub-impedance according to multiple current sub-impedances;

[0031] Among them, the target self-heating power is obtained from the sum of each target sub-self-heating power.

[0032] Optionally, decompose the current excitation signal into waveforms to obtain multiple current excitation waveforms, including:

[0033] Perform a fast Fourier transform on the current excitation signal to obtain multiple current excitation waveforms.

[0034] Optionally, obtain the current excitation signal for self-heating and the current state information of the battery, including:

[0035] Obtain the state information collected by the state information acquisition device for the battery;

[0036] Use the collected state information as the current state information.

[0037] Optionally, obtain the current excitation signal for self-heating and the current state information of the battery, including:

[0038] Obtain the historical impedance and historical excitation signal of the battery determined last time;

[0039] Determine the corresponding historical self-heating power according to the historical amplitude and historical impedance of the historical excitation signal;

[0040] Determine the current state information according to the historical self-heating power, and use the historical excitation signal as the current excitation signal.

[0041] Optionally, after using the target excitation signal as the new current excitation signal to perform excitation adjustment for self-heating the battery, it further includes:

[0042] Determine the self-heating state of the battery. If the self-heating state indicates that the battery currently meets the self-heating exit condition, end the self-heating.

[0043] According to a second aspect of the present application, there is provided a battery self-heating control device, including:

[0044] A data acquisition module for acquiring a current excitation signal for self-heating and current state information of the battery;

[0045] An impedance determination module for determining the current impedance of the battery according to the current excitation signal and the current state information;

[0046] An excitation determination module for determining a target excitation signal for generating a target self-heating power for the current impedance according to the current impedance;

[0047] An excitation adjustment module for using the target excitation signal as a new current excitation signal to perform excitation adjustment for self-heating the battery.

[0048] According to a third aspect of the present application, there is provided a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the battery self-heating control method in any of the above embodiments are implemented.

[0049] According to a fourth aspect of the present application, there is provided a controller, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the battery self-heating control method in any of the above embodiments are implemented.

[0050] According to a fifth aspect of the present application, there is provided a computer program product, including a computer program, and when the computer program is executed by a processor, the steps of the battery self-heating control method in any of the above embodiments are implemented.

[0051] The battery self-heating control method according to the embodiments of the present application can acquire in real time a current excitation signal for self-heating the battery and current state information of the battery, so as to determine the current impedance of the battery, and further can determine a target self-heating power with better self-heating effect for the current impedance and a target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as a new current excitation signal to perform excitation adjustment for self-heating the battery. Through cyclic control, the excitation signal for self-heating is always made to approach the power requirement corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the self-heating process of the battery.

[0052] Other features and advantages of the present application will be described in detail in the subsequent specific implementation section. Description of the Drawings

[0053] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0054] To more fully understand the present application and its beneficial effects, the following will be described in conjunction with the accompanying drawings, where the same reference numerals in the following description represent the same parts.

[0055] Figure 1 is a schematic flowchart of the battery self-heating control method provided in an exemplary embodiment of the present application;

[0056] Figure 2 is a waveform diagram of the excitation signal provided in an exemplary embodiment of the present application;

[0057] Figure 3 is a schematic flowchart of the battery self-heating control method including an exit mechanism provided in an exemplary embodiment of the present application;

[0058] Figure 4 is a schematic structural diagram of the battery self-heating control device provided in an exemplary embodiment of the present application. Detailed Embodiments

[0059] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present application.

[0060] According to the first aspect of the present application, as Figure 1 shown, a battery self-heating control method is provided, including:

[0061] Step 101, obtaining the current excitation signal for self-heating and the current state information of the battery.

[0062] Among them, the excitation signal generally refers to an excitation current, which can be generated in various ways. For example, for the battery architecture of a single battery pack, the corresponding energy storage device can be controlled to generate an oscillating current with the battery pack, and the oscillating current is used as the excitation to heat the internal resistance of the battery pack to achieve the purpose of self-heating. Another example is for the battery architecture of multiple battery packs. Multiple battery packs can be controlled to charge and discharge with each other, and the corresponding charge and discharge currents are used as excitations to heat the internal resistances of the multiple battery packs respectively to achieve the purpose of self-heating.

[0063] Among them, the state information of the battery affects the impedance of the battery itself. When the state information of the battery changes, the corresponding impedance also changes synchronously. Different impedances have different power requirements. For example, the impedance within one impedance range can accept a relatively high power, while the impedance within another impedance range can accept a relatively low power. Therefore, when it is necessary to determine the more suitable power requirement for the battery's impedance in real time, it is necessary to first determine the state information of the battery to determine the impedance of the battery.

[0064] Among them, the state information may include at least one of temperature state information and state of charge information. For example, when the excitation is in a fixed mode, as the self-heating process progresses, the temperature of the battery increases and the corresponding state of charge decreases, which will cause the impedance of the battery to decrease, ultimately reducing the self-heating power and the achieved temperature rise rate.

[0065] Step 102: Determine the current impedance of the battery according to the current excitation signal and the current state information.

[0066] As mentioned in the above steps, the state information of the battery affects the impedance of the battery. In addition, the excitation signal applied to the battery also affects the impedance of the battery. Therefore, when determining the current impedance, in order to ensure the accuracy of the determined impedance, it is necessary to simultaneously consider the excitation signal and the state information.

[0067] Specifically, it can be understood that the excitation signal and the state information can be used as independent variables, and the corresponding impedance can be used as the dependent variable. Thus, based on the known current excitation signal and the current state information, the corresponding current impedance can be determined according to the variation relationship between the excitation signal, the state information, and the impedance.

[0068] Step 103: Determine the target excitation signal for generating the target self-heating power for the current impedance.

[0069] Among them, since different impedances have different power requirements, after determining the current impedance, the self-heating power that it can accept can be determined. Theoretically, the larger the self-heating power within the controllable range, the better. The determined target self-heating power can be the maximum self-heating power that the current impedance can receive, or the second maximum self-heating power, or the third maximum self-heating power, etc.

[0070] Among them, the self-heating power is generated by exciting the internal resistance of the battery with the corresponding excitation signal. Therefore, it can be understood that the target self-heating power and its corresponding target excitation signal are determined synchronously.

[0071] Step 104: Use the target excitation signal as the new current excitation signal to adjust the self-heating excitation of the battery.

[0072] Among them, the self-heating system always excites the internal resistance of the battery based on the latest determined current excitation signal. In step 104, before obtaining the new current excitation signal, the current excitation signal obtained in step 101 will still be used to excite the internal resistance of the battery. After taking the determined target excitation signal as the new current excitation signal, the previous current excitation signal is discarded, and then the new current excitation signal is used to excite the internal resistance of the battery.

[0073] Among them, after obtaining the new current excitation signal, the excitation of the internal resistance of the battery will change, so that the current state information of the battery will change accordingly, and then new current state information is obtained, and finally steps 101 to 104 are repeatedly executed.

[0074] The battery self-heating control method according to the embodiment of the present application can obtain in real time the current excitation signal for self-heating the battery and the current state information of the battery, so as to determine the current impedance of the battery, and then can determine the target self-heating power with better self-heating effect for the current impedance and the target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as the new current excitation signal to adjust the excitation for self-heating the battery. Through cyclic control, the excitation signal for self-heating is always made to approach the power demand corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the self-heating process of the battery.

[0075] Optionally, the current state information includes current temperature state information and current state of charge information; determining the current impedance of the battery according to the current excitation signal and the current state information includes:

[0076] Determine the current frequency of the current excitation signal.

[0077] As mentioned in the above embodiment, the excitation signal applied to the battery will affect the impedance of the battery. Specifically in this embodiment, the excitation signal includes a frequency characteristic, and the internal resistance of the battery will exhibit different impedances when connected to excitation signals of different frequencies. Therefore, after obtaining the current excitation signal, the current frequency of the current excitation signal can be further determined to facilitate subsequent determination of the current impedance of the battery based on independent variables such as the current frequency.

[0078] Determine the current impedance of the battery according to the current frequency, the current temperature state information, and the current state of charge information.

[0079] Among them, as the self-heating process progresses, the obtained current temperature state information of the battery shows an increase in temperature relative to the previous time node, and the obtained current state of charge information of the battery shows a decrease in the state of charge relative to the previous time node.

[0080] Among them, based on the obtained current frequency, current temperature status information, and current state of charge information, as well as the change relationships between the three and the impedance of the battery, the current impedance of the battery can be specifically determined.

[0081] Optionally, determining the current impedance of the battery according to the current frequency, current temperature status information, and current state of charge information includes:

[0082] According to the current frequency, current temperature status information, and current state of charge information, match the corresponding sample frequency, sample temperature status information, and sample state of charge information in the target database constructed based on the electrochemical impedance spectrum of the battery.

[0083] Among them, Electrochemical Impedance Spectroscopy (EIS) is a powerful analysis technique used to study the electrochemical characteristics of batteries by measuring the impedance of the battery at different frequencies. In this embodiment, on the premise that temperature and state of charge have a certain influence on the impedance of the battery, a target database of the mapping relationship of "impedance" - "frequency, temperature, and state of charge" is pre-constructed based on the electrochemical impedance spectrum. In the target database, there are multiple sample frequencies, sample temperature status information, sample state of charge information, and sample impedance, and each set of sample frequency, sample temperature status information, and sample state of charge information is mapped to a sample impedance.

[0084] Among them, after obtaining the current frequency, current temperature status information, and current state of charge information, the corresponding sample frequency, sample temperature status information, and sample state of charge information can be queried and matched in the target database by means of interpolation calculation. It can be understood that when the data richness in the target database is high enough, the sample frequency, sample temperature status information, and sample state of charge information that are exactly the same as the current frequency, current temperature status information, and current state of charge information can be matched in the target database; when the data richness in the target database is not high, the similarity between the matched sample frequency, sample temperature status information, and sample state of charge information and the actual current frequency, current temperature status information, and current state of charge information is the highest compared to other sample frequencies, sample temperature status information, and sample state of charge information.

[0085] Determine the sample impedance corresponding to the sample frequency, sample temperature status information, and sample state of charge information as the current impedance.

[0086] Among them, the mapping relationship in the target database is obtained in advance through reasonable test methods and real test data, so the matched sample impedance can be determined as the real current impedance.

[0087] Among them, as a supplement, electrochemical impedance spectroscopy performs an AC impedance test on the target battery at 0.1 - 10,000 Hz on an electrochemical workstation, and the impedance result obtained from the test is |Z| = (Re^2 + Rm^2)^0.5; where |Z| is the modulus value of the impedance, Re is the real part of the AC internal resistance of the battery, and Rm is the imaginary part of the AC internal resistance of the battery.

[0088] Optionally, determining a target excitation signal for generating a target self-heating power for the current impedance includes:

[0089] Obtaining a plurality of candidate excitation signals;

[0090] Determining the candidate amplitude of each candidate excitation signal;

[0091] According to the current impedance and each candidate amplitude, determining the candidate self-heating power corresponding to each candidate amplitude.

[0092] Among them, as mentioned in the above embodiments, when determining the target excitation signal, it is specifically determined by the self-heating power that the excitation signal can generate. For the calculation of the self-heating power of the battery, it is necessary to calculate the product of the impedance and the amplitude of the excitation signal according to the impedance of the battery and the amplitude of the excitation signal to determine the corresponding self-heating power. Therefore, before determining the self-heating power, it is necessary to calculate the self-heating power corresponding to the excitation signal on the premise of "having an excitation signal".

[0093] Specifically, a plurality of candidate excitation signals can be respectively obtained, so as to determine the candidate self-heating power corresponding to each candidate amplitude according to the current impedance and the candidate amplitude of each candidate excitation signal.

[0094] Determining one of the candidate self-heating powers exceeding the preset power among the plurality of candidate self-heating powers as the target self-heating power and determining the corresponding candidate excitation signal as the target excitation signal.

[0095] Among them, after obtaining a plurality of candidate self-heating powers, one of the candidate self-heating powers can be determined as the target self-heating power by comparing their magnitudes. Undoubtedly, the candidate excitation signal used to generate this candidate self-heating power is also simultaneously determined as the target excitation signal.

[0096] Among them, in order to maximize the self-heating effect, the candidate self-heating power with the maximum power can be determined as the target self-heating power and the corresponding candidate excitation signal can be determined as the target excitation signal.

[0097] Optionally, obtaining a plurality of candidate excitation signals includes:

[0098] Obtaining a plurality of initial excitation signals;

[0099] Determining the initial frequency of each initial excitation signal;

[0100] Determine multiple initial excitation signals whose initial frequencies in multiple initial excitation signals meet a preset frequency range as candidate excitation signals.

[0101] Among them, as mentioned in the above embodiments, the self-heating power of the battery needs to be within a controllable range, which is mainly affected by the frequency of the excitation signal. During the process of the battery achieving self-heating, the frequency range it can accept is limited. When exceeding the frequency range, there are relatively large safety hazards.

[0102] Therefore, in this embodiment, the selected candidate excitation signals are all excitation signals whose frequencies satisfy the corresponding frequency range. Specifically, a larger number of initial excitation signals can be obtained first, and then the initial frequencies of each initial excitation signal are compared with the corresponding preset frequency range respectively, and the initial excitation signals whose initial frequencies meet the preset frequency range are determined as candidate excitation signals.

[0103] By screening the frequencies of the excitation signals, it can be ensured that when determining the target excitation signal subsequently, only the magnitude of the self-heating power that can be generated needs to be considered.

[0104] Specifically, determine the boundary of the self-heating current amplitude and frequency combination through the actual measurement results of the battery, the charge and discharge strategy, and the allowable use range of the self-heating related components, and consider the frequency factor therein, so as to obtain the corresponding preset frequency range.

[0105] As a supplement, in other embodiments, it is also possible not to perform frequency screening first, but directly consider the self-heating power that can be generated. If the candidate frequency of the candidate excitation signal corresponding to the maximum candidate self-heating power does not meet the preset frequency range, then abandon this candidate excitation signal, and then consider other candidate excitation signals.

[0106] The concepts of the above two methods are basically the same, and both require frequency screening. The difference lies only in the timing of frequency screening. By pre-screening the frequency, it is possible to avoid calculating the self-heating power of candidate excitation signals that do not meet the requirements subsequently, and can save the calculation amount to a certain extent.

[0107] Optionally, determine the current impedance of the battery according to the current excitation signal and the current state information, including:

[0108] Perform waveform decomposition on the current excitation signal to obtain multiple current excitation waveforms.

[0109] Among them, usually, the waveform of the actual excitation signal is not regular. The waveform diagram of a certain excitation signal can be as Figure 2As shown, it is difficult to directly determine its frequency and / or amplitude. Therefore, in this embodiment, the acquired current excitation signal needs to be decomposed in waveform to obtain a plurality of relatively regular current excitation waveforms.

[0110] According to each current excitation waveform and the current state information, determine the current sub-impedance corresponding to each current excitation waveform.

[0111] Among them, each current excitation waveform obtained by decomposition has a corresponding frequency and amplitude. Therefore, based on the frequency of each current excitation waveform and the current state information, the current sub-impedance exhibited by the battery under the excitation of each current excitation waveform can be determined respectively.

[0112] Obtain the current impedance according to a plurality of current sub-impedances.

[0113] Among them, the set of a plurality of current sub-impedances is used as the current impedance.

[0114] Of course, in other embodiments, if the waveform of the actual excitation signal itself is regular, there is no need to perform waveform decomposition, and its frequency and / or amplitude can be directly determined.

[0115] Optionally, determining a target excitation signal for generating a target self-heating power for the current impedance includes:

[0116] Determine the target excitation signals corresponding to a plurality of target sub-excitation waveforms respectively used to generate target sub-self-heating powers for each current sub-impedance according to a plurality of current sub-impedances;

[0117] Among them, the target self-heating power is obtained by the sum of each target sub-self-heating power.

[0118] Among them, when the determined current impedance is a set composed of a plurality of current sub-impedances, it is necessary to determine, for each current sub-impedance, the sub-heating power that the corresponding excitation waveform in the excitation signal can generate for it. Thus, by comparing the magnitudes of the sums of each set of self-heating powers, the corresponding excitation signal can be determined. The finally determined excitation signal can be used as the target excitation signal, the plurality of sub-excitation waveforms it contains can be used as the target excitation waveforms, and the sum of the self-heating powers that each target sub-excitation waveform can generate for the corresponding current sub-impedance can be used as the target self-heating power.

[0119] Optionally, decomposing the current excitation signal in waveform to obtain a plurality of current excitation waveforms includes:

[0120] Perform a fast Fourier transform on the current excitation signal to obtain a plurality of current excitation waveforms.

[0121] Among them, the fast Fourier transform can convert the current excitation signal from the time domain to the frequency domain, so as to decompose multiple current excitation waveforms with different frequencies.

[0122] During the waveform decomposition process, for any excitation signal, the decomposition result through the fast Fourier transform can be expressed as: where x(t) is the excitation signal, A 0 is the DC component, A n is the AC current amplitude component of each order.

[0123] During the self-heating power calculation process, for any excitation signal, its corresponding self-heating power can be expressed as: where P is the self-heating power, A 1 , A 2 , A 3 etc. are the current amplitudes of each order component of the excitation signal, and |Z1|, |Z2|, |Z3|, etc. are the impedances corresponding to each order component. Since each order component processed by the fast Fourier transform is a sine signal, the effective value of the current amplitude needs to be divided by for conversion. Through the above calculation method, after traversing each candidate excitation signal, the self-heating power that each candidate excitation signal can generate can be determined, and then the target excitation signal that generates the target self-heating power can be determined through power comparison.

[0124] Optionally, obtaining the current excitation signal for self-heating and the current state information of the battery includes:

[0125] Obtaining the state information collected by the state information collection device for the battery;

[0126] Taking the collected state information as the current state information.

[0127] Among them, for the state information of the battery, including the temperature state information and the state of charge information, both can be obtained by direct collection. Specifically, the system can pre-configure the corresponding state information collection device; for temperature, the state information collection device can include a temperature sensor, etc.; for the state of charge, the state information collection device can include a battery management system, etc.

[0128] Optionally, obtaining the current excitation signal for self-heating and the current state information of the battery includes:

[0129] Obtaining the historical impedance and historical excitation signal of the battery determined last time;

[0130] Determining the corresponding historical self-heating power according to the historical amplitude and historical impedance of the historical excitation signal;

[0131] Determine the current state information according to the historical self-heating power, and use the historical excitation signal as the current excitation signal.

[0132] Among them, as the self-heating process progresses, the temperature of the battery will increase and the state of charge will decrease, and the degree of change depends on the self-heating power generated by the excitation signal used to excite the battery.

[0133] Therefore, in this embodiment, in addition to directly collecting the state information in the above embodiment, the corresponding historical self-heating power can also be determined based on the historical impedance and historical excitation signal obtained from the previous control.

[0134] First, the self-heating power combined with the heat dissipation parameters of the battery can characterize the temperature rise rate of the battery, and then the changed temperature can be determined by combining the corresponding duration.

[0135] Second, the self-heating power can characterize the degree of consumption of the state of charge of the battery, and then the changed state of charge can be determined by combining the corresponding duration.

[0136] As Figure 3 shown, optionally, after using the target excitation signal as the new current excitation signal to adjust the excitation for the self-heating of the battery, it further includes:

[0137] Step 105, determine the self-heating state of the battery. If the self-heating state indicates that the battery currently meets the self-heating exit condition, end the self-heating.

[0138] Among them, the cyclic control reflected in the above embodiment is to enable the battery to maintain a good self-heating effect throughout the self-heating process. In this embodiment, when the temperature of the battery reaches the preset temperature, it means that the corresponding self-heating is completed, and there is no need to perform the cyclic control of self-heating adjustment anymore. Therefore, it can be used as the heating exit condition to exit the cyclic control and end the self-heating.

[0139] To make the above embodiments clearer, the above embodiments are now combined and described. Specifically, the present application provides a battery self-heating control method, including:

[0140] S1. Determine the current excitation signal, current temperature state information, and current state of charge information for self-heating;

[0141] S2. Process the current excitation signal through fast Fourier transform to obtain the waveform information of multiple alternating current self-heating pulse current waveforms;

[0142] S3. Traverse the entire frequency range according to the frequencies in the multiple waveform information, the current temperature state information, and the current state of charge information, and based on the target database constructed from the electrochemical impedance spectrum of the lithium-ion battery, to obtain the current impedance of the battery;

[0143] S4. Determine a target excitation signal capable of generating a target self-heating power based on the current impedance, and use the target excitation signal as the new current excitation signal to adjust the amplitude and frequency of the current; calculate the current self-heating power of the battery based on the amplitudes in the multiple waveform information and the multiple current sub-impedances in the current impedance, determine the temperature change and state of charge change of the battery based on the current self-heating power, and determine the changed temperature state information and state of charge information based on the temperature change and state of charge change;

[0144] S5. Re-execute S1;

[0145] S6. When the self-heating exit condition is met, end the self-heating process.

[0146] In summary, in the present application, when the battery temperature rises due to the self-heating process, the AC impedance Z = Re + iRm of the battery decreases, and the self-heating temperature rise rate will decrease. The parameters after fast Fourier transform processing are used to adjust the frequency of the self-heating waveform, so that the sum of the products of the square of the current amplitude of each order sine component and the corresponding impedance remains the largest. This is the process of frequency optimization and amplitude optimization of the self-heating waveform. The above method keeps the self-heating power at the maximum at all times, and finally achieves the purpose of increasing the self-heating temperature rise rate and shortening the self-heating time.

[0147] According to the second aspect of the present application, as Figure 4 shown, a battery self-heating control device is provided, including:

[0148] A data acquisition module 201, configured to acquire a current excitation signal for self-heating and the current state information of the battery;

[0149] An impedance determination module 202, configured to determine the current impedance of the battery according to the current excitation signal and the current state information;

[0150] An excitation determination module 203, configured to determine a target excitation signal for generating a target self-heating power for the current impedance according to the current impedance;

[0151] An excitation adjustment module 204, configured to use the target excitation signal as the new current excitation signal to perform excitation adjustment for self-heating the battery.

[0152] The battery self-heating control device according to the embodiment of the present application can obtain in real time the current excitation signal for self-heating the battery and the current state information of the battery, thereby determining the current impedance of the battery, and further being able to determine the target self-heating power with better self-heating effect for the current impedance and the target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as the new current excitation signal to adjust the excitation for self-heating the battery. Through cyclic control, the excitation signal for self-heating is always made to approach the power demand corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the entire self-heating process of the battery.

[0153] According to the third aspect of the present application, there is provided a computer-readable storage medium having stored thereon a computer program, and when the computer program is executed by a processor, the steps of the battery self-heating control method in any of the above embodiments are implemented.

[0154] The battery self-heating control method implemented when the computer-readable storage medium according to the embodiment of the present application is executed by a processor can obtain in real time the current excitation signal for self-heating the battery and the current state information of the battery, thereby determining the current impedance of the battery, and further being able to determine the target self-heating power with better self-heating effect for the current impedance and the target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as the new current excitation signal to adjust the excitation for self-heating the battery. Through cyclic control, the excitation signal for self-heating is always made to approach the power demand corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the entire self-heating process of the battery.

[0155] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can 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.) containing computer-usable program code.

[0156] The present application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate for implementing in the process Figure 1 one process or multiple processes and / or blocksFigure 1 means for the functions specified in one or more boxes.

[0157] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction means that implements the functions specified in one Figure 1 one or more processes and / or boxes Figure 1 means for the functions specified in one or more boxes.

[0158] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus, such that a series of operational steps are performed on the computer or other programmable apparatus to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one Figure 1 one or more processes and / or boxes Figure 1 means for the functions specified in one or more boxes.

[0159] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0160] The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM) and / or non-volatile memory such as read-only memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

[0161] Computer-readable media includes both permanent and non-permanent, removable and non-removable media, which can be implemented by any method or technology for storing information. The information may be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile discs (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media such as modulated data signals and carrier waves.

[0162] According to a fourth aspect of the present application, there is provided a controller on which a computer program is stored, and when the computer program is executed by a processor, the steps of the battery self-heating control method in any of the above embodiments are implemented.

[0163] The battery self-heating control method executed by the controller according to the embodiments of the present application can obtain in real time the current excitation signal for self-heating the battery and the current state information of the battery, so as to determine the current impedance of the battery, and further determine the target self-heating power with better self-heating effect for the current impedance and the target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as the new current excitation signal to adjust the excitation for self-heating the battery. Through cyclic control, the excitation signal used for self-heating is always made to approach the power demand corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the entire self-heating process of the battery.

[0164] According to a fifth aspect of the present application, there is provided a computer program product including a computer program, and when the computer program is executed by a processor, the steps of the battery self-heating control method in any of the above embodiments are implemented.

[0165] The battery self-heating control method implemented when the computer program product according to the embodiments of the present application is processed and executed can obtain in real time the current excitation signal for self-heating the battery and the current state information of the battery, so as to determine the current impedance of the battery, and further determine the target self-heating power with better self-heating effect for the current impedance and the target excitation signal corresponding to the target self-heating power. Finally, the target excitation signal is used as the new current excitation signal to adjust the excitation for self-heating the battery. Through cyclic control, the excitation signal used for self-heating is always made to approach the power demand corresponding to the impedance of the battery, ensuring that a good self-heating effect can be maintained throughout the entire self-heating process of the battery.

[0166] In the description of the present application, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0167] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0168] Among the embodiments, implementation manners and related technical features of the present application, they can be combined and replaced with each other without conflict.

[0169] The above are only the preferred embodiments of the present application and do not impose any formal restrictions on the present application. In the embodiments of the present application, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant content of other embodiments. However, as long as it does not depart from the content of the technical solution of the present application, any brief modifications, equivalent changes, and decorations made to the above embodiments based on the technical essence of the present application still fall within the scope of the technical solution of the present application.

Claims

1. A battery self-heating control method, characterized in that: include: Obtaining a current excitation signal for self-heating and current status information of the battery; Determining a current impedance of the battery according to the current excitation signal and the current state information; Determining, according to the current impedance, a target excitation signal for generating a target self-heating power for the current impedance; The target excitation signal is used as a new current excitation signal to adjust the excitation of the battery for self-heating.

2. The battery self-heating control method according to claim 1, characterized in that: The current state information includes current temperature state information and current charge state information; and determining the current impedance of the battery according to the current excitation signal and the current state information includes: Determining a current frequency of the current excitation signal; The current impedance of the battery is determined according to the current frequency, the current temperature state information and the current state of charge information.

3. The battery self-heating control method according to claim 2, characterized in that: The determining the current impedance of the battery according to the current frequency, the current temperature state information and the current state of charge information includes: According to the current frequency, the current temperature state information and the current state of charge information, matching corresponding sample frequency, sample temperature state information and sample state of charge information in a target database constructed based on the electrochemical impedance spectrum of the battery; A sample impedance corresponding to the sample frequency, the sample temperature state information, and the sample charge state information is determined as the current impedance.

4. The battery self-heating control method according to claim 1, characterized in that: The step of determining, according to the current impedance, a target excitation signal for generating a target self-heating power for the current impedance comprises: Acquire multiple stimulus signals to be selected; Determining a candidate amplitude of each of the candidate excitation signals; Determine, according to the current impedance and each of the amplitudes to be selected, a heating power to be selected corresponding to each of the amplitudes to be selected; A to-be-selected heating power exceeding a preset power among the plurality of to-be-selected heating powers is determined as the target self-heating power, and a corresponding to-be-selected excitation signal is determined as the target excitation signal.

5. The battery self-heating control method according to claim 4, characterized in that: The step of obtaining a plurality of excitation signals to be selected comprises: Acquiring multiple initial excitation signals; Determining an initial frequency of each of the initial excitation signals; A plurality of initial excitation signals whose initial frequencies conform to the preset frequency range among the plurality of initial excitation signals are determined as the excitation signals to be selected.

6. The battery self-heating control method according to claim 1, characterized in that: The determining the current impedance of the battery according to the current excitation signal and the current state information includes: Performing waveform decomposition on the current excitation signal to obtain multiple current excitation waveforms; Determine, according to each of the current excitation waveforms and the current state information, a current sub-impedance corresponding to each of the current excitation waveforms; The current impedance is obtained according to the multiple current sub-impedances.

7. The battery self-heating control method according to claim 6, characterized in that: The step of determining, according to the current impedance, a target excitation signal for generating a target self-heating power for the current impedance comprises: Determining, according to the plurality of current sub-impedances, target excitation signals corresponding to a plurality of target sub-excitation waveforms respectively used to generate a target sub-self-heating power for each of the current sub-impedances; The target self-heating power is obtained by summing up the target sub-self-heating powers.

8. The battery self-heating control method according to claim 6 or 7, characterized in that: The step of performing waveform decomposition on the current excitation signal to obtain a plurality of current excitation waveforms includes: Performing a fast Fourier transform on the current excitation signal to obtain a plurality of current excitation waveforms.

9. The battery self-heating control method according to claim 1, characterized in that: The obtaining of the current excitation signal for self-heating and the current state information of the battery includes: Acquire status information collected by a status information collection device for the battery; The collected state information is used as the current state information.

10. The battery self-heating control method according to claim 1, characterized in that: The obtaining of the current excitation signal for self-heating and the current state information of the battery includes: Obtain the historical impedance and historical excitation signal of the battery determined last time; Determining a corresponding historical self-heating power according to the historical amplitude of the historical excitation signal and the historical impedance; The current state information is determined according to the historical self-heating power, and the historical excitation signal is used as the current excitation signal.

11. The battery self-heating control method according to claim 1, characterized in that: After taking the target excitation signal as a new current excitation signal to adjust the excitation of the battery for self-heating, the method further includes: The self-heating state of the battery is determined, and if the self-heating state indicates that the battery currently meets a self-heating exit condition, the self-heating is terminated.

12. A battery self-heating control device, characterized in that: include: A data acquisition module, used to acquire a current excitation signal for self-heating and current status information of the battery; an impedance determination module, configured to determine a current impedance of the battery according to the current excitation signal and the current state information; an excitation determination module, configured to determine, according to the current impedance, a target excitation signal for generating a target self-heating power for the current impedance; The excitation adjustment module is used to use the target excitation signal as a new current excitation signal to perform excitation adjustment for self-heating of the battery.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the processor executes the computer program, the steps of the battery self-heating control method according to any one of claims 1 to 11 are implemented.

14. A controller having a computer program stored thereon, characterized in that: When the processor executes the computer program, the steps of the battery self-heating control method according to any one of claims 1 to 11 are implemented.

15. A computer program product comprising a computer program, characterized in that When the processor executes the computer program, the steps of the battery self-heating control method according to any one of claims 1 to 11 are implemented.

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