Internal temperature measurement method and apparatus for battery, and electronic device and storage medium

Abstract

Disclosed are an internal temperature measurement method and apparatus for a battery, and an electronic device and a storage medium. The method comprises: acquiring a surface temperature of a battery, and determining a temperature interval in which the surface temperature is located; when the surface temperature is in a first temperature interval, selecting from an excitation frequency selection section an excitation frequency corresponding to the surface temperature, wherein the excitation frequency selection section includes a plurality of excitation frequencies; generating an excitation signal on the basis of the excitation frequency corresponding to the surface temperature, and outputting the excitation signal to the battery, so as to acquire a response signal fed back by the battery in response to the excitation signal; determining a battery impedance of the battery on the basis of the excitation signal and the response signal; and determining an internal temperature on the basis of the battery impedance.

Description

Battery internal temperature detection method and device, electronic equipment and storage medium

[0001] Reference of Related Applications

[0002] The present disclosure claims the full right of priority of the Chinese Invention Patent Application No. 202410467578.1, filed on April 18, 2024, and entitled “Battery internal temperature detection method and device, electronic equipment and storage medium”, and incorporates it by reference in its entirety.

[0003] TECHNICAL FIELD

[0004] The present disclosure generally relates to the field of batteries, and more particularly to a battery internal temperature detection method and device, electronic equipment and storage medium.

[0005] BACKGROUND

[0006] During fast charging of a battery, due to the increase in current density and the increase in internal electrochemical reaction rate, it can cause extreme temperature rise, which in turn threatens the safety of the battery. Accurate and timely judgment of the internal temperature change of the battery is of great significance to solve the thermal runaway problem of the battery in the fast charging process and to improve the performance and safety of the battery.

[0007] In order to obtain accurate and real-time internal temperature of the battery, the internal temperature of the battery can be detected by establishing a mapping relationship between the battery impedance and the internal temperature of the battery. The battery impedance is related to the SOC (State of Charge) of the battery, the internal temperature of the battery, the SOH (State of Health) of the battery and the excitation frequency.

[0008] At present, in general engineering applications, a specific excitation frequency can be selected to reduce the influence of the SOH and SOC of the battery on the battery impedance. However, the change of the battery temperature will affect the degree of influence of the SOH and SOC of the battery on the battery impedance. For example, under low temperature conditions, there is a good corresponding relationship between the battery impedance and the internal temperature of the battery, but as the temperature rises, the degree of influence of the SOH and SOC of the battery on the battery impedance is strengthened, which weakens the corresponding relationship between the battery impedance and the internal temperature of the battery. If the internal temperature of the battery is estimated based on the battery impedance generated by the excitation frequency under low temperature conditions under high temperature conditions, it is difficult to eliminate the influence of the SOH and SOC of the battery on the battery impedance, resulting in inaccurate estimation of the internal temperature of the battery.

[0009] In summary, using only the battery impedance generated based on a single excitation frequency to estimate the internal temperature of the battery in the entire temperature range can result in significant errors, and the estimated internal temperature of the battery is not accurate.

[0010] SUMMARY

[0011] In a first aspect, the disclosure provides a method for detecting an internal temperature of a battery, comprising:

[0012] obtaining a surface temperature of the battery, and determining a temperature interval in which the surface temperature is located;

[0013] in a case where the surface temperature is located in a first temperature interval, selecting an excitation frequency corresponding to the surface temperature in an excitation frequency selection section; wherein the excitation frequency selection section contains a plurality of excitation frequencies;

[0014] generating an excitation signal according to the excitation frequency corresponding to the surface temperature, and outputting the excitation signal to the battery, to obtain a response signal fed back by the battery in response to the excitation signal;

[0015] determining a battery impedance of the battery according to the excitation signal and the response signal; and

[0016] determining the internal temperature according to the battery impedance.

[0017] In a second aspect, the disclosure provides a device for detecting an internal temperature of a battery, comprising:

[0018] a first obtaining module configured to obtain a surface temperature of the battery, and determine a temperature interval in which the surface temperature is located;

[0019] a selecting module configured to, in a case where the surface temperature is located in a first temperature interval, select an excitation frequency corresponding to the surface temperature in an excitation frequency selection section; wherein the excitation frequency selection section contains a plurality of excitation frequencies;

[0020] a generating module configured to generate an excitation signal according to the excitation frequency corresponding to the surface temperature, and output the excitation signal to the battery, to obtain a response signal fed back by the battery in response to the excitation signal;

[0021] a first determining module configured to determine a battery impedance of the battery according to the excitation signal and the response signal; and

[0022] a second determining module configured to determine the internal temperature according to the battery impedance.

[0023] In a third aspect, the disclosure provides an electronic device, comprising: at least one communication interface; at least one bus connected with the at least one communication interface; at least one processor connected with the at least one bus; and at least one memory connected with the at least one bus, wherein the processor is configured to execute the method for detecting an internal temperature of a battery provided by the disclosure.

[0024] In a fourth aspect, the present disclosure provides a computer storage medium storing computer executable instructions for implementing the method for detecting the internal temperature of a battery.

[0025] In some embodiments, the excitation frequency corresponding to the surface temperature of the battery is selected according to the surface temperature of the battery, an excitation signal is generated according to the selected excitation frequency, the excitation signal is input into the battery to obtain a response signal fed back by the battery, the battery impedance of the battery is determined based on the excitation signal and the response signal, and the internal temperature of the battery is determined according to the battery impedance.

[0026] In some embodiments, the excitation frequency of the excitation signal input into the internal part of the battery is determined based on different surface temperatures of the battery, the internal temperature of the battery is estimated by avoiding using a single excitation signal with a single excitation frequency, the internal temperature of the battery can be better estimated in combination with the actual working condition of the battery, the correlation between the internal temperature of the battery and the battery impedance is improved, the estimation error of the internal temperature of the battery is reduced, and the estimation accuracy of the internal temperature of the battery is improved.

[0027] BRIEF DESCRIPTION OF DRAWINGS

[0028] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the description, further serve to explain the principles behind the present disclosure.

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required by the embodiments will be briefly introduced as follows. Obviously, for those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

[0030] One or more embodiments are exemplarily illustrated by pictures in the drawings corresponding thereto, and these exemplary illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, unless otherwise specified. The drawings do not constitute a proportional limitation.

[0031] FIG. 1 is a flowchart of a method for detecting the internal temperature of a battery according to an embodiment of the present disclosure.

[0032] FIG. 2 is a structural diagram of a detection system in the method for detecting the internal temperature of a battery according to an embodiment of the present disclosure.

[0033] FIG. 3 is a flowchart of the method for detecting the internal temperature of a battery according to an embodiment of the present disclosure.

[0034] FIG. 4 is a flowchart of a determination of an excitation frequency selection section in the method for detecting the internal temperature of a battery according to an embodiment of the present disclosure.

[0035] FIG. 5 is a structural schematic diagram of an internal temperature detection device of a battery according to an embodiment of the present disclosure.

[0036] FIG. 6 is a structural schematic diagram of an electronic device according to an embodiment of the present disclosure.

[0037] DETAILED DESCRIPTION

[0038] The objectives, technical solutions and advantages of the embodiments of the present disclosure will become more apparent after a brief description of the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present disclosure.

[0039] The following disclosure provides many different embodiments or examples for implementing different structures of the present disclosure. In order to simplify the present disclosure, the components and settings of specific examples are described below. Of course, they are only examples and the purpose is not to limit the present disclosure. In addition, reference numerals and / or letters can be repeated in different examples. Such repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed.

[0040] In some embodiments, the present disclosure provides a method for detecting the internal temperature of a battery, which can reduce the estimation error of the internal temperature of the battery and improve the estimation accuracy of the internal temperature of the battery.

[0041] FIG. 1 is a flowchart of a method for detecting the internal temperature of a battery according to an embodiment of the present disclosure. Referring to FIG. 1, the method for detecting the internal temperature of a battery provided by the present disclosure includes:

[0042] S1: obtaining the surface temperature of the battery and determining the temperature interval in which the surface temperature is located;

[0043] S2: in the case that the surface temperature is in the first temperature interval, selecting the excitation frequency corresponding to the surface temperature in the excitation frequency selection section; wherein the excitation frequency selection section contains a plurality of excitation frequencies;

[0044] S3: generating an excitation signal according to the excitation frequency corresponding to the surface temperature and outputting the excitation signal to the battery to obtain a response signal fed back by the battery in response to the excitation signal;

[0045] S4: determining the battery impedance of the battery according to the excitation signal and the response signal; and

[0046] S5: determining the internal temperature according to the battery impedance.

[0047] In some embodiments, the method for detecting the internal temperature of the battery can be applied to the BMS (Battery Management System) of the battery, and in particular, can be applied to the AFE (Analog Front End) in the BMS.

[0048] The method for detecting the internal temperature of the battery can be implemented by the detection system shown in FIG. 2. Referring to FIG. 2, a thermosensitive element can be arranged on the surface of the battery, the surface temperature of the battery can be obtained by the thermosensitive element arranged on the surface of the battery, the thermosensitive element is used to monitor the surface temperature of the battery in real time, and the monitored surface temperature can be transmitted to the processing core in the AFE through the sensor interface arranged on the AFE, so as to obtain the surface temperature. The thermosensitive element can be a thermocouple or a thermal resistor.

[0049] In some embodiments, after obtaining the surface temperature detected by the thermosensitive element, the processing core determines the temperature interval in which the surface temperature is located based on numerical comparison.

[0050] In some embodiments, when the temperature interval in which the surface temperature is located is determined as the first temperature interval, the excitation frequency corresponding to the surface temperature is determined from the excitation frequency selection section. The excitation frequency selection section contains a plurality of possible excitation frequencies. The excitation frequency selection section can be a numerical interval, for example, [0.1KHZ, 1KHZ], any excitation frequency in the interval (for example, 0.12KHZ) can be selected, or it can be an excitation frequency data set, for example, (0.1KHZ, 0.2KHZ, 0.3KHZ,..., 1KHZ), and the excitation frequencies in the data set can be selected (for example, 0.3KHZ).

[0051] The excitation frequencies in the excitation frequency selection section have a certain corresponding relationship with the surface temperature. Such a corresponding relationship is a pre-set corresponding relationship. Based on such a corresponding relationship, the excitation frequency corresponding to the surface temperature can be selected when the surface temperature is determined.

[0052] In some embodiments, the corresponding relationship between the excitation frequency and the surface temperature can exist in the form of interval correspondence. When the surface temperature is determined to be in the first temperature interval, the sub-temperature interval in which the surface temperature is located is further determined. The sub-temperature interval is contained in the first temperature interval, and each sub-temperature interval corresponds to a specific excitation frequency in the excitation frequency section.

[0053] Referring to FIG. 3, the first temperature interval can be divided into four temperature sub-intervals, the first temperature interval is [T1, T5), the first temperature sub-interval is [T1, T2), the second temperature sub-interval is [T2, T3), the third temperature sub-interval is [T3, T4), and the fourth temperature sub-interval is [T4, T5). When the surface temperature is in the first temperature sub-interval, the excitation frequency f1 in the excitation frequency segment is selected as the excitation frequency corresponding to the surface temperature; when the surface temperature is in the second temperature sub-interval, the excitation frequency f2 in the excitation frequency segment is selected as the excitation frequency corresponding to the surface temperature; when the surface temperature is in the third temperature sub-interval, the excitation frequency f3 in the excitation frequency segment is selected as the excitation frequency corresponding to the surface temperature; and when the surface temperature is in the fourth temperature sub-interval, the excitation frequency f4 in the excitation frequency segment is selected as the excitation frequency corresponding to the surface temperature.

[0054] Based on the experimental test, it is known that the higher the surface temperature of the battery is, the better the corresponding relationship between the larger excitation frequency and the internal temperature of the battery. Therefore, in some embodiments, in order to enable the selected excitation frequency to better detect the internal temperature of the battery at the surface temperature corresponding to the excitation frequency, f1 < f2 < f3 < f4 is set.

[0055] In some embodiments, after obtaining the surface temperature of the battery and determining the temperature interval in which the surface temperature is located, the method further comprises:

[0056] In the case that the surface temperature is in the second temperature interval or the third temperature interval, the surface temperature is determined as the internal temperature; wherein the values in the second temperature interval are all less than the values in the first temperature interval, and the values in the third temperature interval are all greater than the values in the first temperature interval.

[0057] Continuing to refer to FIG. 3, the second temperature interval is (-∞, T1), and the third temperature interval is [T5, ∞).

[0058] In some embodiments, before obtaining the surface temperature of the battery, the method further comprises:

[0059] Obtaining a first excitation frequency selection segment; wherein the correlation between the excitation frequency in the first excitation selection segment and the internal temperature is greater than a first set threshold;

[0060] Obtaining a second excitation frequency selection segment; wherein the correlation between the excitation frequency in the second excitation selection segment and the state of charge of the battery is less than a second set threshold;

[0061] Obtaining a third excitation frequency selection segment; wherein the correlation between the excitation frequency in the third excitation selection segment and the state of health of the battery is less than a third set threshold; and

[0062] The intersection of the first excitation frequency selection section, the second excitation frequency selection section, and the third excitation frequency selection section is determined as the excitation frequency selection section.

[0063] In some embodiments, the first excitation frequency selection section, the second excitation frequency selection section, and the third excitation frequency selection section are data pre-built in the AFE, and the first excitation frequency selection section, the second excitation frequency selection section, and the third excitation frequency selection section are measured by the technician through experiments.

[0064] Since the correlation between the excitation frequency in the first excitation selection section and the internal temperature is greater than the first set threshold, the correlation between the excitation frequency in the second excitation selection section and the state of charge of the battery is less than the second set threshold, and the correlation between the excitation frequency in the third excitation selection section and the state of health of the battery is less than the third set threshold, the excitation frequency in the excitation frequency section all satisfies the following conditions: the correlation between the excitation frequency and the internal temperature is greater than the first set threshold, the correlation between the excitation frequency and the state of charge of the battery is less than the second set threshold, and the correlation between the excitation frequency and the state of health of the battery is less than the third set threshold.

[0065] Through the above-mentioned implementation scheme for obtaining the excitation frequency selection section, it can be ensured that the excitation frequency selected by the battery when estimating the internal temperature all satisfies the following conditions: strong correlation with the internal temperature and weak correlation with the state of charge and weak correlation with the state of health, so that the estimation of the internal temperature of the battery can be more accurate.

[0066] In some embodiments, the first excitation frequency selection section is determined based on a first calibration test, and the first calibration test includes:

[0067] Obtaining first calibration data of a plurality of test batteries at a plurality of test temperature points, the state of charge and the state of health of the plurality of test batteries being consistent, the first calibration data being an excitation frequency and impedance characteristic value data set of the test battery at each test temperature point;

[0068] Calculating the standard deviation of each first calibration data; and

[0069] Comparing the standard deviations of each first calibration data to determine the first excitation frequency selection section.

[0070] In some embodiments, the test batteries include a plurality of test batteries, the SOC of all the test batteries is adjusted to the same specified value, and the SOH of all the test batteries is adjusted to the same specified value; the plurality of test batteries are respectively placed in different high and low temperature ovens, the test temperature points of the test batteries are adjusted by controlling the high and low temperature ovens, after the temperature in the high and low temperature ovens is adjusted to the test temperature points, the test batteries are left to stand for 3 hours, so that the temperature of the test batteries reaches thermal equilibrium with the temperature in the high and low temperature ovens, and the test temperature points can be selected as -20℃, -10℃, 0℃, 10℃, 25℃ and 45℃; the test batteries are input with excitation signals of an excitation frequency, the excitation frequency is 0.1KHZ-1KHZ, the feedback signals of the test batteries are read, and the battery impedance is determined based on the excitation signals and the feedback signals; first calibration data is obtained, the first calibration data is the excitation frequency-battery impedance data of each test battery under the same SOC and SOH; the standard deviation of each first calibration data is calculated; the standard deviations of each first calibration data are compared, and a frequency range in which the test temperature has the greatest impact on the first calibration data is selected as a first excitation frequency selection range.

[0071] In some embodiments, taking the impedance amplitude of the battery impedance as an example, the standard deviation of the first calibration data is calculated by the following formula:

[0072] wherein, Z1, Z2,..., Z n is the impedance amplitude of the battery under different test temperatures at a given SOC and SOH, ΔZ is the average value of Z1, Z2,..., Z n , and σ is the standard deviation of the first calibration data.

[0073] In some embodiments, the second excitation frequency selection range is determined based on a second calibration test, and the second calibration test includes:

[0074] Second calibration data of the plurality of test batteries under a plurality of test states of charge is obtained, the test temperature points and the health states of the plurality of test batteries are consistent, and the second calibration data is an excitation frequency and impedance characteristic value data set of the test batteries under each test state of charge;

[0075] The standard deviation of each second calibration data is calculated; and

[0076] The standard deviations of each second calibration data are compared to determine the second excitation frequency selection range.

[0077] In some embodiments, the third excitation frequency selection range is determined based on a third calibration test, and the third calibration test includes:

[0078] obtaining third calibration data of a plurality of test batteries at a plurality of test health states, the test temperature points of the plurality of test batteries being consistent with the state of charge, the third calibration data being the excitation frequency and the impedance characteristic value data set of the test battery at each test health state;

[0079] calculating the standard deviation of each third calibration data; and

[0080] comparing the standard deviation of each third calibration data to determine the third excitation frequency selection segment.

[0081] The specific process of the second calibration test and the third calibration test is similar to that of the first calibration test. The second calibration test takes the state of charge of the battery as the variable to determine the influence of the state of charge of the battery on the impedance of the battery. The third calibration test takes the health state of the battery as the variable to determine the influence of the health state of the battery on the impedance of the battery.

[0082] Referring to FIG. 4, FIG. 4 describes the determination process of the excitation frequency selection segment.

[0083] The first excitation frequency selection segment (fa, fb) is determined by the first calibration test, the second excitation frequency selection segment (fc, fd) is determined by the second calibration test, and the third excitation frequency selection segment (fe, ff) is determined by the third calibration test. The intersection of the first excitation frequency selection segment, the second excitation frequency selection segment and the third excitation frequency selection segment is determined to be the excitation frequency selection segment (fn, fm), so as to select the excitation frequency set which has strong correlation with the internal temperature of the battery, weak correlation with the state of charge of the battery and weak correlation with the health state of the battery.

[0084] It should be noted that, in order to ensure the accuracy of each calibration test, the consistency of the test battery used in the above-mentioned first calibration test, second calibration test and third calibration test is relatively high.

[0085] In some embodiments, continuing to refer to FIG. 2, the AFE is also connected to the positive and negative poles of the battery at the same time. After the excitation frequency is determined based on the surface temperature, the excitation signal is generated according to the determined excitation frequency and output to one pole of the battery. After receiving the excitation signal, the battery will feedback a response signal at the other pole, and the feedback signal of the battery is obtained.

[0086] It can be understood that the excitation signal can be input to the positive or negative pole of the battery, and the response signal is output at the other pole of the excitation signal input, that is, if the excitation signal is input to the positive pole of the battery, the response signal is fed back at the negative pole of the battery, and vice versa, if the excitation signal is input to the negative pole of the battery, the response signal is fed back at the positive pole of the battery. In FIG. 2, the excitation signal is input to the positive pole of the battery as an example.

[0087] In some embodiments, the excitation signal input to the battery is a sinusoidal perturbation signal (current or potential signal) with a frequency of an excitation frequency, the battery feeds back a response signal after receiving the excitation signal, the response signal is also a sinusoidal signal (current or potential signal), and the ratio of the excitation signal to the response signal is determined as the battery impedance of the battery.

[0088] In some embodiments, there is a certain correspondence between the battery impedance and the internal temperature of the battery, and the internal temperature of the current battery is determined according to the battery impedance on the basis of the known battery impedance.

[0089] In some embodiments, the internal temperature is determined according to the battery impedance, comprising:

[0090] determining an impedance characteristic value according to the battery impedance;

[0091] obtaining a characteristic value-temperature mapping table corresponding to the excitation frequency; wherein the characteristic value-temperature mapping table is used to describe the mapping relationship between the impedance characteristic value and the internal temperature under the current excitation frequency; and

[0092] looking up the internal temperature corresponding to the impedance characteristic value in the characteristic value-temperature mapping table according to the impedance characteristic value.

[0093] In some embodiments, the impedance characteristic value of the battery impedance can be any one of the impedance amplitude, the impedance phase angle, the impedance real part or the impedance imaginary part.

[0094] In some embodiments, the confirmation of the excitation frequency of the excitation signal is realized, and for each excitation signal of a specific excitation frequency, there is a corresponding characteristic value-temperature mapping table, the characteristic value-temperature mapping table reflects the mapping relationship between the impedance characteristic value and the internal temperature of the battery, there are multiple impedance characteristic values in the characteristic value-temperature mapping table, and each impedance characteristic value corresponds to an internal temperature, and the characteristic value-temperature mapping table is measured by technicians based on experiments.

[0095] On the basis of the known battery impedance characteristic value and the characteristic value-temperature mapping table corresponding to the excitation frequency, the internal temperature of the battery corresponding to the impedance characteristic value can be obtained by looking up the impedance characteristic value in the characteristic value-temperature mapping table.

[0096] In some embodiments, a frequency corresponding to the surface temperature of the battery is selected according to the surface temperature of the battery, an excitation signal is generated according to the selected excitation frequency, the excitation signal is input into the battery to obtain a response signal fed back by the battery, the battery impedance of the battery is determined based on the excitation signal and the response signal, and the internal temperature of the battery is determined according to the battery impedance. The excitation frequency in the excitation frequency range has a strong correlation with the internal temperature of the battery and a weak correlation with the state of charge and the state of health of the battery. Different excitation frequencies are selected at different surface temperatures of the battery to minimize the influence of the state of charge and the state of health of the battery on the internal temperature of the battery, improve the correlation between the internal temperature of the battery and the battery impedance, and thus reduce the estimation error of the internal temperature of the battery and improve the estimation accuracy of the internal temperature of the battery.

[0097] Corresponding to the above method embodiments, the disclosure also provides a device for detecting the internal temperature of a battery. Referring to FIG. 5, the device includes:

[0098] The first acquisition module 501 is configured to acquire the surface temperature of the battery and determine the temperature interval in which the surface temperature is located.

[0099] The selection module 502 is configured to select an excitation frequency corresponding to the surface temperature in the excitation frequency selection section when the surface temperature is in the first temperature interval. The excitation frequency selection section includes a plurality of excitation frequencies.

[0100] The generation module 503 is configured to generate an excitation signal according to the excitation frequency corresponding to the surface temperature and output the excitation signal to the battery to obtain a response signal fed back by the battery in response to the excitation signal.

[0101] The first determination module 504 is configured to determine the battery impedance of the battery according to the excitation signal and the response signal.

[0102] The second determination module 505 is configured to determine the internal temperature according to the battery impedance.

[0103] In some embodiments, the device further includes:

[0104] The third determination module is configured to determine the surface temperature as the internal temperature when the surface temperature is in the second temperature interval or the third temperature interval. The values in the second temperature interval are all less than the values in the first temperature interval, and the values in the third temperature interval are all greater than the values in the first temperature interval.

[0105] In some embodiments, the second determination module 505 further includes:

[0106] The determination unit is configured to determine the impedance characteristic value according to the battery impedance.

[0107] The acquisition unit is configured to acquire an amplitude-temperature mapping table corresponding to the excitation frequency; wherein the characteristic value-temperature mapping table is used to describe a mapping relationship between the impedance characteristic value and the internal temperature at the current excitation frequency; and

[0108] The searching unit is configured to search for the internal temperature corresponding to the impedance characteristic value in the characteristic value-temperature mapping table according to the impedance characteristic value.

[0109] In some embodiments, the device further comprises:

[0110] The second acquisition module is configured to acquire a first excitation frequency selection section; wherein the correlation between the excitation frequency and the internal temperature in the first excitation selection section is greater than a first set threshold;

[0111] The third acquisition module is configured to acquire a second excitation frequency selection section; wherein the correlation between the excitation frequency and the state of charge of the battery in the second excitation selection section is less than a second set threshold;

[0112] The fourth acquisition module is configured to acquire a third excitation frequency selection section; wherein the correlation between the excitation frequency and the state of health of the battery in the third excitation selection section is less than a third set threshold; and

[0113] The fourth determination module is configured to determine the intersection of the first excitation frequency selection section, the second excitation frequency selection section and the third excitation frequency selection section as the excitation frequency selection section.

[0114] In some embodiments, the first excitation frequency selection section is determined based on a first calibration test, and the first calibration test comprises:

[0115] Acquiring first calibration data of a plurality of test batteries at a plurality of test temperature points, the state of charge and the state of health of the plurality of test batteries being consistent, the first calibration data being a set of excitation frequency and impedance characteristic value data of the test battery at each test temperature point;

[0116] Calculating the standard deviation of each first calibration data, the standard deviation of the first calibration data being used to describe the correlation between the excitation frequency and the internal temperature; and

[0117] Selecting the excitation frequency corresponding to the first calibration data with the standard deviation greater than the first set threshold to determine the first excitation frequency selection section.

[0118] In some embodiments, the second excitation frequency selection section is determined based on a second calibration test, and the second calibration test comprises:

[0119] Acquiring second calibration data of a plurality of test batteries at a plurality of test states of charge, the test temperature points and the state of health of the plurality of test batteries being consistent, the second calibration data being a set of excitation frequency and impedance characteristic value data of the test battery at each test state of charge;

[0120] calculate a standard deviation of each second calibration data, the standard deviation of the second calibration data being used to describe the correlation between the excitation frequency and the state of charge; and

[0121] select the excitation frequency corresponding to the second calibration data with the standard deviation less than a second set threshold value, to determine a second excitation frequency selection section.

[0122] In some embodiments, the third excitation frequency selection section is determined based on a third calibration test, the third calibration test comprising:

[0123] obtaining third calibration data of a plurality of test batteries at a plurality of test states of health, the test temperature points of the plurality of test batteries being consistent with the state of charge, the third calibration data being the excitation frequency and the impedance feature value data set of the test battery at each test state of health;

[0124] calculating a standard deviation of each third calibration data, the standard deviation of the third calibration data being used to describe the correlation between the excitation frequency and the state of health; and

[0125] select the excitation frequency corresponding to the third calibration data with the standard deviation less than a third set threshold value, to determine a third excitation frequency selection section.

[0126] As shown in FIG. 6, an embodiment of the present disclosure provides an electronic device, which includes a processor 601, a communication interface 602, a memory 603 and a communication bus 604, wherein the processor 601, the communication interface 602 and the memory 603 complete mutual communication through the communication bus 604,

[0127] The memory 603 is configured to store a computer program.

[0128] In some embodiments, the processor 601 is configured to execute the program stored on the memory 603, to implement the battery internal temperature detection method described in the present disclosure, which comprises:

[0129] obtaining the surface temperature of the battery and determining the temperature interval in which the surface temperature is located;

[0130] in the case that the surface temperature is in the first temperature interval, selecting the excitation frequency corresponding to the surface temperature in the excitation frequency selection section; wherein the correlation between the excitation frequency in the excitation frequency selection section and the internal temperature of the battery is greater than a first set threshold value, and the correlation with the state of charge of the battery is less than a second set threshold value, and the correlation with the state of health of the battery is less than a third set threshold value;

[0131] generating an excitation signal according to the excitation frequency corresponding to the surface temperature, and outputting the excitation signal to the battery to obtain a response signal fed back by the battery in response to the excitation signal;

[0132] determining a battery impedance of the battery according to the excitation signal and the response signal; and

[0133] determining the internal temperature according to the battery impedance.

[0134] An embodiment of the present disclosure further provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the internal temperature detection method of the battery.

[0135] The apparatus embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment.

[0136] From the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a general hardware platform, and of course can also be implemented by hardware. Based on such understanding, the above technical solutions can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0137] It should be understood that the terms used herein are for the purpose of describing specific example embodiments only and are not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order in which they are described, unless specifically indicated as such. It is also to be understood that additional or alternative steps can be employed.

[0138] The foregoing is merely illustrative of the various implementations of the present disclosure and the general principles thereof. Numerous modifications can be made to these illustrations, and equivalents can be substituted therefor, without departing from the scope of the present disclosure. The specific embodiments commensurate with the specific application are intended to be illustrative only and not limiting of the scope of the application as set forth in the following claims.

Claims

1. A method for detecting an internal temperature of a battery, comprising: obtaining a surface temperature of the battery and determining a temperature interval in which the surface temperature is located, wherein the temperature interval comprises a preset first temperature interval; in a case where the surface temperature is in the first temperature interval, obtaining an excitation frequency selection section of the battery, and selecting an excitation frequency corresponding to the surface temperature in the excitation frequency selection section, wherein the excitation frequency selection section comprises a plurality of excitation frequencies; generating an excitation signal according to the excitation frequency corresponding to the surface temperature and outputting the excitation signal to the battery to obtain a response signal fed back by the battery in response to the excitation signal; determining a battery impedance of the battery according to the excitation signal and the response signal; and determining the internal temperature according to the battery impedance.

2. The method of claim 1, wherein, After obtaining the surface temperature of the battery and determining the temperature interval in which the surface temperature is located, the temperature interval comprises a second temperature interval and a third temperature interval, and the method further comprises: in a case where the surface temperature is in the second temperature interval or the third temperature interval, determining the surface temperature as the internal temperature, wherein values in the second temperature interval are all less than values in the first temperature interval, and values in the third temperature interval are all greater than values in the first temperature interval.

3. The method of claim 1, wherein, Determining the internal temperature according to the battery impedance comprises: determining an impedance characteristic value according to the battery impedance, wherein the impedance characteristic value can be any one of an impedance amplitude, an impedance phase angle, an impedance real part or an impedance imaginary part; obtaining a characteristic value-temperature mapping table corresponding to the excitation frequency, wherein the characteristic value-temperature mapping table is used to describe a mapping relationship between the impedance characteristic value and the internal temperature under the current excitation frequency; and finding the internal temperature corresponding to the impedance characteristic value in the characteristic value-temperature mapping table according to the impedance characteristic value. 4.The method of claim 2, wherein determining the internal temperature according to the battery impedance comprises: determining an impedance characteristic value according to the battery impedance; the impedance characteristic value can be any one of an impedance amplitude, an impedance phase angle, an impedance real part or an impedance imaginary part; obtaining a characteristic value-temperature mapping table corresponding to the excitation frequency, wherein the characteristic value-temperature mapping table is used to describe a mapping relationship between the impedance characteristic value and the internal temperature under the current excitation frequency; and finding the internal temperature corresponding to the impedance characteristic value in the characteristic value-temperature mapping table according to the impedance characteristic value. 5.The method of claim 1, wherein before obtaining the surface temperature of the battery, the method further comprises: obtaining a first excitation frequency selection section, wherein the excitation frequencies in the first excitation selection section have a correlation with the internal temperature greater than a first set threshold; obtaining a second excitation frequency selection section, wherein the excitation frequencies in the second excitation selection section have a correlation with a state of charge of the battery less than a second set threshold. ​ obtaining a third excitation frequency selection segment; wherein the excitation frequencies in the third excitation selection segment have a correlation with the state of health of the battery that is less than a third set threshold; and determining an intersection of the first excitation frequency selection segment, the second excitation frequency selection segment, and the third excitation frequency selection segment as the excitation frequency selection segment.

6. The method of claim 2, wherein prior to obtaining the surface temperature of the battery, the method further comprises: obtaining a first excitation frequency selection segment; wherein the excitation frequencies in the first excitation selection segment have a correlation with the internal temperature that is greater than a first set threshold; obtaining a second excitation frequency selection segment; wherein the excitation frequencies in the second excitation selection segment have a correlation with the state of charge of the battery that is less than a second set threshold; obtaining a third excitation frequency selection segment; wherein the excitation frequencies in the third excitation selection segment have a correlation with the state of health of the battery that is less than a third set threshold; and determining an intersection of the first excitation frequency selection segment, the second excitation frequency selection segment, and the third excitation frequency selection segment as the excitation frequency selection segment.

7. The method of claim 3, wherein prior to obtaining the surface temperature of the battery, the method further comprises: obtaining a first excitation frequency selection segment; wherein the excitation frequencies in the first excitation selection segment have a correlation with the internal temperature that is greater than a first set threshold; obtaining a second excitation frequency selection segment; wherein the excitation frequencies in the second excitation selection segment have a correlation with the state of charge of the battery that is less than a second set threshold; obtaining a third excitation frequency selection segment; wherein the excitation frequencies in the third excitation selection segment have a correlation with the state of health of the battery that is less than a third set threshold; and determining an intersection of the first excitation frequency selection segment, the second excitation frequency selection segment, and the third excitation frequency selection segment as the excitation frequency selection segment.

8. The method of claim 4, wherein prior to obtaining the surface temperature of the battery, the method further comprises: obtaining a first excitation frequency selection segment; wherein the excitation frequencies in the first excitation selection segment have a correlation with the internal temperature that is greater than a first set threshold; obtaining a second excitation frequency selection segment; wherein the excitation frequencies in the second excitation selection segment have a correlation with the state of charge of the battery that is less than a second set threshold; obtaining a third excitation frequency selection segment; wherein the excitation frequencies in the third excitation selection segment have a correlation with the state of health of the battery that is less than a third set threshold; and determining an intersection of the first excitation frequency selection segment, the second excitation frequency selection segment, and the third excitation frequency selection segment as the excitation frequency selection segment.

9. The method of any of claims 5-7, wherein the first excitation frequency selection segment is determined based on a first calibration test, the first calibration test comprising: obtaining first calibration data of a plurality of test batteries at a plurality of test temperature points, the state of charge and the state of health of the plurality of test batteries being consistent, the first calibration data being the excitation frequency and the impedance characteristic value data set of the test battery at each of the test temperature points; calculating a standard deviation of each of the first calibration data; comparing the standard deviation of each of the first calibration data to determine the first excitation frequency selection section.

10. The method of any one of claims 5-7, wherein the second excitation frequency selection section is determined based on a second calibration test, the second calibration test comprising: obtaining second calibration data of a plurality of test batteries at a plurality of test state of charge, the test temperature points and the state of health of the plurality of test batteries being consistent, the second calibration data being the excitation frequency and the impedance characteristic value data set of the test battery at each of the test state of charge; calculating a standard deviation of each of the second calibration data; comparing the standard deviation of each of the second calibration data to determine the second excitation frequency selection section.

11. The method of any one of claims 5-7, wherein the third excitation frequency selection section is determined based on a third calibration test, the third calibration test comprising: obtaining third calibration data of a plurality of test batteries at a plurality of test state of health, the test temperature points and the state of charge of the plurality of test batteries being consistent, the third calibration data being the excitation frequency and the impedance characteristic value data set of the test battery at each of the test state of health; calculating a standard deviation of each of the third calibration data; comparing the standard deviation of each of the third calibration data to determine the third excitation frequency selection section. at least one communication interface; at least one bus connected to the at least one communication interface; at least one processor connected to the at least one bus; 12. An electronic device comprising: at least one memory connected to the at least one bus, wherein the processor is configured to implement the method for detecting the internal temperature of the battery according to any one of claims 1-8. The processor is configured to implement the method for detecting the internal temperature of the battery according to claim 9. The processor is configured to implement the method for detecting the internal temperature of the battery according to claim 10. The processor is configured to implement the method for detecting the internal temperature of the battery according to claim 11.

13. The electronic device of claim 12, wherein, 16. A computer storage medium storing computer executable instructions for implementing the method for detecting the internal temperature of the battery according to any one of claims 1-8.

14. The electronic device of claim 12, wherein, The computer executable instructions are for implementing the method for detecting the internal temperature of the battery according to claim 9.

15. The electronic device of claim 12, wherein, The computer executable instructions are for implementing the method for detecting the internal temperature of the battery according to claim 10. The computer executable instructions are for implementing the method for detecting the internal temperature of the battery according to claim 11.

17. The computer storage medium of claim 16, wherein, ​ 18. The computer storage medium of claim 16, wherein, ​ 19. The computer storage medium of claim 16, wherein, ​

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