Method, device and electronic device for determining battery internal resistance

Abstract

The present application provides a method, device, and electronic device for determining the internal resistance of a battery. The method comprises: obtaining an initial data sample set of a battery under test during a single charge within a specified time period; wherein each data sample in the initial data sample set includes at least a charging time, a SOC value, a current value, and a voltage value; performing data cleaning on the initial data sample set according to a preset rule to obtain a first sample pair set comprising multiple first sample pairs; wherein each first sample pair is composed of two data samples with adjacent charging times in the initial data sample set; and determining a first internal resistance value of the battery under test during a single charge within the specified time period based on the first sample pair set. The present application can improve the accuracy of the battery internal resistance determination result while reducing the cost required to determine the battery internal resistance.

Description

Technical Field

[0001] The present application relates to the field of battery detection technology, and in particular to a method, device, and electronic device for determining the internal resistance of a battery. Background Art

[0002] Internal resistance is an important technical indicator for measuring battery performance. Under normal circumstances, batteries with low internal resistance have strong discharge capacity, while batteries with high internal resistance have weak discharge capacity. A battery's internal resistance consists of both ohmic resistance and polarization resistance, both of which vary with battery usage conditions. Ohmic resistance obeys Ohm's law, while polarization resistance does not. Therefore, ohmic resistance is easier to estimate than polarization resistance.

[0003] Currently, common methods for determining battery internal resistance include: directly measuring the battery internal resistance through external devices, calculating the internal resistance based on battery parameters during a single charge (such as SOC, current, and voltage), etc. However, existing internal resistance measurement methods have the following disadvantages: (1) Directly measuring the battery internal resistance through external devices is expensive and has problems with poor stability and low accuracy; (2) Calculating the internal resistance based on battery parameters during a single charge has large errors, and the single charge process is greatly affected by the battery usage conditions. Summary of the Invention

[0004] In view of this, the purpose of the present application is to provide a method, device and electronic device for determining the internal resistance of a battery, so as to improve the accuracy of the battery internal resistance determination result while reducing the cost required for determining the battery internal resistance.

[0005] In a first aspect, an embodiment of the present application provides a method for determining the internal resistance of a battery, the method comprising: obtaining an initial data sample set of a battery to be tested during a single charging process within a specified time period; wherein each data sample in the initial data sample set includes at least a charging time, an SOC value, a current value, and a voltage value; performing data cleaning on the initial data sample set according to preset rules to obtain a first sample pair set comprising multiple first sample pairs; wherein each first sample pair consists of two data samples adjacent to each other at the charging time in the initial data sample set; and determining the first internal resistance value of the battery to be tested during a single charging process within the specified time period based on the first sample pair set.

[0006] In combination with the first aspect, an embodiment of the present application provides a first possible implementation method of the first aspect, wherein the step of performing data cleaning on the initial data sample set according to preset rules to obtain a first sample pair set containing multiple first sample pairs includes: forming a first initial sample pair from two data samples with adjacent charging moments in the initial data sample set to obtain a first initial sample pair set containing multiple first initial sample pairs; calculating the charging moment interval, current difference and voltage difference of each first initial sample pair based on the charging moments, current values ​​and voltage values ​​of the two data samples in each first initial sample pair; and taking the first initial sample pair in the first initial sample pair set that meets the first preset condition as the first sample pair to obtain a first sample pair set.

[0007] In combination with the first aspect, an embodiment of the present application provides a second possible implementation of the first aspect, wherein satisfying the first preset condition includes at least one of the following: the charging moment interval does not exceed the preset time threshold; the SOC values ​​of the two data samples in the same first initial sample pair are less than the preset SOC threshold; the current value at the latter charging moment in the same first initial sample pair is less than the preset current threshold; the current difference is within the preset current range; the voltage difference is within the preset voltage range.

[0008] In combination with the first aspect, an embodiment of the present application provides a third possible implementation of the first aspect, wherein the step of determining the first internal resistance value of the battery to be tested during a single charging process within the specified time period based on the first sample pair set includes: calculating the first instantaneous internal resistance of each first sample pair based on the voltage difference and current difference of each first sample pair in the first sample pair set; and determining the first internal resistance value of the battery to be tested during a single charging process within the specified time period based on all the calculated first instantaneous internal resistances.

[0009] In combination with the first aspect, an embodiment of the present application provides a fourth possible implementation of the first aspect, wherein the step of determining the first internal resistance value of the battery to be tested during a single charging process within the specified time period based on all the calculated first instantaneous internal resistances includes: calculating the average value of all the first instantaneous internal resistances based on all the calculated first instantaneous internal resistances; and determining the calculated average value as the first internal resistance value of the battery to be tested during a single charging process within the specified time period.

[0010] In combination with the first aspect, an embodiment of the present application provides a fifth possible implementation of the first aspect, wherein the battery to be tested is suitable for a target vehicle; the data sample also includes the identity information of the target vehicle; the battery to be tested has undergone multiple charging processes within a specified time period; the method also includes: obtaining the first internal resistance value of the battery to be tested during each charging process within the specified time period; and determining the second internal resistance value of the target vehicle within the specified time period based on the identity information and the multiple first internal resistance values ​​obtained.

[0011] In combination with the first aspect, an embodiment of the present application provides a sixth possible implementation of the first aspect, wherein the target vehicle is a vehicle of a target model within the specified time period in the designated charging area; there are multiple target vehicles within the specified time period in the designated charging area; the data sample also includes the area information of the designated charging area and the model information of the target model; the method also includes: obtaining the second internal resistance value of all target vehicles within the designated charging area; and determining the third internal resistance value of the target model within the designated charging area within the specified time period based on the area information, the model information and the multiple second internal resistance values ​​obtained.

[0012] In combination with the first aspect, an embodiment of the present application provides a seventh possible implementation of the first aspect, wherein the method further includes: calculating a discrete degree parameter of all acquired second internal resistance values; and judging whether the second internal resistance value of each target vehicle is abnormal based on the third internal resistance value and the discrete degree parameter.

[0013] In a second aspect, an embodiment of the present application further provides a device for determining the internal resistance of a battery, the device comprising: a data acquisition module for acquiring an initial data sample set of a battery to be tested during a single charging process within a specified time period; wherein the initial data sample set includes data samples at multiple different charging moments; wherein the data samples include at least charging moments, SOC values, current values, and voltage values; a data cleaning module for performing data cleaning on the initial data sample set according to preset rules to obtain a first sample pair set comprising multiple first sample pairs; wherein each first sample pair consists of two data samples adjacent to each other at the charging moment in the initial data sample set; a first internal resistance value determination module for determining the first internal resistance value of the battery to be tested during a single charging process within the specified time period based on the first sample pair set.

[0014] In a third aspect, an embodiment of the present application further provides an electronic device, comprising a processor and a memory, wherein the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the above-mentioned method for determining the internal resistance of the battery.

[0015] The embodiments of the present application provide a method, device, and electronic device for determining the internal resistance of a battery. The method includes: first obtaining an initial data sample set of a battery to be tested during a single charging process within a specified time period (each data sample in the initial data sample set includes at least the charging time, SOC value, current value, and voltage value), then performing data cleaning on the initial data sample set according to preset rules to obtain a first sample pair set containing multiple first sample pairs (each first sample pair consists of two data samples with adjacent charging times in the initial data sample set), and then determining the first internal resistance value of the battery to be tested during the single charging process within the specified time period based on the first sample pair set. Using the above technology, after obtaining battery parameter data samples during a single charging process of a battery within a period of time, these data samples will be cleaned according to specific rules, thereby obtaining multiple sample pairs consisting of two data samples adjacent to each other at the charging moment. Finally, the internal resistance value of the battery during a single charging process during this period of time is determined based on these sample pairs. This operation method only requires simple data processing of the battery's charging data over a period of time to obtain the internal resistance of the battery during this period. Compared with the method of directly measuring the battery internal resistance through an external device, the cost required to determine the battery internal resistance can be reduced. In addition, this operation method fully considers the real-time changes of the battery parameters during the charging process when determining the battery internal resistance, thereby improving the accuracy of the battery internal resistance determination result.

[0016] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description or be understood by practicing the present application. The objectives and other advantages of the present application are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0017] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 A flowchart of a method for determining the internal resistance of a battery provided in an embodiment of the present application;

[0020] Figure 2 A schematic structural diagram of a device for determining battery internal resistance provided in an embodiment of the present application;

[0021] Figure 3 A schematic structural diagram of another device for determining battery internal resistance provided in an embodiment of the present application;

[0022] Figure 4 A schematic structural diagram of another device for determining battery internal resistance provided in an embodiment of the present application;

[0023] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0025] Internal resistance is an important technical indicator for measuring battery performance. Under normal circumstances, batteries with small internal resistance have strong discharge capabilities, while batteries with large internal resistance have weak discharge capabilities. The internal resistance of a battery includes ohmic internal resistance and polarization internal resistance. For lithium-ion batteries, the ohmic internal resistance of the battery mainly includes the resistance formed by the resistance encountered when lithium ions pass through the electrolyte, the diaphragm resistance, the resistance of the electrolyte-electrode interface, and the resistance of the collector (copper and aluminum foil, electrodes). The polarization internal resistance includes the electrochemical polarization resistance and the resistance caused by concentration polarization during the process of lithium ion insertion, deinsertion, and ion diffusion transfer. Both ohmic internal resistance and polarization internal resistance will vary with different battery usage conditions. Among them, the ohmic internal resistance obeys Ohm's law, while the polarization internal resistance does not obey Ohm's law. Therefore, the ohmic internal resistance is easier to estimate than the polarization internal resistance.

[0026] Currently, common methods for determining battery internal resistance include: directly measuring the battery internal resistance through external devices, calculating the internal resistance based on battery parameters during a single charge (such as SOC, current, and voltage), etc. However, existing internal resistance measurement methods have the following disadvantages: (1) Directly measuring the battery internal resistance through external devices is expensive and has problems with poor stability and low accuracy; (2) Calculating the internal resistance based on battery parameters during a single charge has large errors, and the single charge process is greatly affected by the battery usage conditions.

[0027] Based on this, the embodiments of the present application provide a method, device, and electronic device for determining the internal resistance of a battery, which can improve the accuracy of the battery internal resistance determination result while reducing the cost required to determine the battery internal resistance.

[0028] The battery internal resistance mentioned in the embodiments of the present application refers to the ohmic internal resistance and has nothing to do with the polarization internal resistance.

[0029] To facilitate understanding of this embodiment, a method for determining the internal resistance of a battery disclosed in an embodiment of the present application is first introduced in detail. Figure 1 The flowchart of a method for determining the internal resistance of a battery is shown, and the method may include the following steps:

[0030] Step S102 , obtaining an initial data sample set of a single charging process of the battery under test within a specified time period; wherein each data sample in the initial data sample set includes at least a charging time, an SOC value, a current value, and a voltage value.

[0031] The battery to be tested can be a single battery or a battery pack composed of multiple cells, and there is no limitation on this. Taking the battery to be tested as a battery pack mounted on an electric vehicle as an example, as a feasible implementation method, when an electric vehicle charges the battery pack at a charging pile, the charging pile collects the battery parameters of the battery pack at different charging moments in real time. The battery parameters may include SOC value, current value, and voltage value, etc.; since the voltage value collected by the charging pile is the maximum single cell voltage value of the battery pack, in order to further determine the battery with the largest single cell voltage in the battery pack, the above battery parameters may also include the number of the battery with the largest single cell voltage in the battery pack; after the battery pack of the electric vehicle is charged, the charging pile stores the battery parameter data of the electric vehicle from the start to the end of charging. This part of data can be directly obtained through the existing charging pile data collector, and the data belonging to the same charging moment in this part of the data is saved as a data sample, so that multiple data samples at different charging moments are obtained, and these data samples constitute an initial sample set.

[0032] Step S104 , performing data cleaning on the initial data sample set according to a preset rule to obtain a first sample pair set including a plurality of first sample pairs; wherein each first sample pair is composed of two data samples with adjacent charging times in the initial data sample set.

[0033] The above preset rules can be specifically defined according to the charging time, SOC value, current value and voltage value of the data sample, and are not limited to this.

[0034] For ease of operation, the above step S104 may be specifically operated in the following manner:

[0035] (1) Two data samples at adjacent charging moments in the initial data sample set are grouped into a first initial sample pair, thereby obtaining a first initial sample pair set including a plurality of the first initial sample pairs.

[0036] For ease of description, three consecutive charging moments in a charging process are defined herein as t1, t2, and t3, where t1 is adjacent to t2 and t2 is the moment after t1, and t2 is adjacent to t3 and t3 is the moment after t2; the data samples of these three charging moments are defined as sample 1, sample 2, and sample 3; sample 1 and sample 2 are combined into sample pair A, and sample 2 and sample 3 are combined into sample pair B; the data samples of other charging moments in this charging process are processed in a similar manner, thereby obtaining multiple sample pairs (i.e., the above-mentioned first initial sample pairs), which are then combined into a sample pair set (i.e., the above-mentioned first initial sample pair set).

[0037] (2) According to the charging moments, current values, and voltage values ​​of the two data samples in each first initial sample pair, the charging moment interval, current difference, and voltage difference of each first initial sample pair are calculated.

[0038] Continuing with the previous example, define the current values ​​of sample 1, sample 2, and sample 3 as I1, I2, and I3, respectively, define the voltage values ​​of sample 1, sample 2, and sample 3 as U1, U2, and U3, respectively, and the charging time interval of sample pair A is ΔT A =t2-t1, the current difference ΔI of sample pair A A =I2-I1, the voltage difference ΔU of sample pair A A = U2-U1, the charging time interval ΔT of sample pair B B =t3-t2, the current difference ΔI of sample pair A B =I3-I2, voltage difference ΔU of sample pair B B = U3 - U2; and calculate the charging time interval, current difference, and voltage difference of other sample pairs in this charging process in a similar manner.

[0039] (3) The first initial sample pair in the first initial sample pair set that meets the first preset condition is taken as the first sample pair to obtain the first sample pair set.

[0040] As a feasible operation mode, each time an initial sample pair is obtained, it is determined whether the initial sample pair meets the first preset condition. If yes (i.e., the initial sample pair meets the first preset condition), the initial sample pair is retained as the first sample pair; if not (i.e., the initial sample pair does not meet the first preset condition), the initial sample pair is eliminated.

[0041] In practical applications, considering that changes in polarization internal resistance can interfere with the calculation of ohmic internal resistance, the first preset condition can be defined as meeting at least one of the following: the interval between charging moments does not exceed a preset time threshold; the SOC values ​​of two data samples in the same first initial sample pair are less than a preset SOC threshold; the current value at the subsequent charging moment in the same first initial sample pair is less than a preset current threshold; the current difference is within a preset current range, and the voltage difference is within a preset voltage range. The preset time threshold, preset SOC threshold, preset current threshold, preset current range, and preset voltage range can be determined based on actual conditions and are not limited thereto.

[0042] Continuing from the previous example, we get ΔT A , ΔI A , ΔU A , ΔT B , ΔI B , ΔU B Finally, if sample pair A meets the first preset condition but sample pair B does not meet the first preset condition, sample pair A is retained as the first sample pair, and sample pair B is eliminated.

[0043] As a specific application example, the above-mentioned first preset condition can be set to satisfy all of the following conditions at the same time: the charging time interval does not exceed 30s, the SOC values ​​of the two data samples in the same first initial sample pair are less than 80%, the current value of the latter charging moment in the same first initial sample pair is less than 10A, the current difference is in the range of 10A to 100A, and the voltage difference is in the range of 0V to 1V.

[0044] Under the constraints of the first preset condition, the interval between two adjacent charging moments is relatively short, the battery current change amplitude and voltage change amplitude in this interval are relatively small, and the battery SOC value and current value are not very large. At this time, the interference caused by the change of polarization internal resistance on the calculation of ohmic internal resistance can be ignored, so the interval time can be regarded as a relatively stable charging process. Based on this, the multiple sample pairs obtained by the above-mentioned operation methods (1) to (3) can be used to accurately determine the battery internal resistance of the battery during a single charging process.

[0045] Step S106 : determining a first internal resistance value of the battery to be tested during a single charging process within the specified time period according to the first sample pair set.

[0046] For ease of operation, the above step S106 can specifically adopt the following operation method from step 1 to step 2:

[0047] Step 1: Calculate the first instantaneous internal resistance of each first sample pair in the first sample pair set according to the voltage difference and the current difference of each first sample pair.

[0048] Continuing with the previous example, after retaining sample pair A as the first sample pair, the first instantaneous internal resistance of sample pair A is The first instantaneous internal resistances of other first sample pairs during the current charging process are calculated in a similar manner, thereby obtaining the first instantaneous internal resistance of each first sample pair during the current charging process.

[0049] Step 2: Determine a first internal resistance value of the battery under test during a single charge within the specified time period based on the calculated first instantaneous internal resistance.

[0050] As a feasible operation mode, the average value of all the first instantaneous internal resistances can be calculated based on all the calculated first instantaneous internal resistances; and the calculated average value is determined as the first internal resistance value of the battery under test during a single charging process within the specified time period.

[0051] The above average value may be an arithmetic average, a weighted average, a square average, etc., which may be determined according to actual conditions and is not limited thereto. Taking the above average value as an arithmetic average as an example, the first internal resistance value of the battery under test during a single charge process may be calculated using the following formula:

[0052]

[0053] Among them, R represents the first internal resistance value of the battery under test during the charging process, R i represents the first instantaneous internal resistance of the i-th first sample pair during this charging process, and n represents the number of first sample pairs during this charging process.

[0054] The above-mentioned method for determining the internal resistance of a battery provided in an embodiment of the present application includes: first obtaining an initial data sample set of a single charging process of the battery to be tested within a specified time period (each data sample in the initial data sample set includes at least the charging time, SOC value, current value and voltage value), then performing data cleaning on the initial data sample set according to preset rules to obtain a first sample pair set containing multiple first sample pairs (each first sample pair consists of two data samples adjacent to the charging time in the initial data sample set), and then determining the first internal resistance value of the battery to be tested during the single charging process within the specified time period based on the first sample pair set. Using the above technology, after obtaining battery parameter data samples during a single charging process of a battery within a period of time, these data samples will be cleaned according to specific rules, thereby obtaining multiple sample pairs consisting of two data samples adjacent to each other at the charging moment. Finally, the internal resistance value of the battery during a single charging process during this period of time is determined based on these sample pairs. This operation method only requires simple data processing of the battery's charging data over a period of time to obtain the internal resistance of the battery during this period. Compared with the method of directly measuring the battery internal resistance through an external device, the cost required to determine the battery internal resistance can be reduced. In addition, this operation method fully considers the real-time changes of the battery parameters during the charging process when determining the battery internal resistance, thereby improving the accuracy of the battery internal resistance determination result.

[0055] In actual applications, the battery under test can be used in a target vehicle. To facilitate identification of the source of the data sample by relevant personnel, the data sample can also include the identity information of the target vehicle. This identity is a unique identifier used to characterize the identity of the target vehicle, and can specifically be a vehicle frame number, license plate number, etc., without limitation. Based on this, in the case where the battery under test undergoes multiple charging processes within a specified time period, the method can also include the following operations: obtaining a first internal resistance value of the battery under test during each charging process within the specified time period; and determining a second internal resistance value of the target vehicle within the specified time period based on the identity information and the multiple first internal resistance values ​​obtained.

[0056] As a feasible implementation method, the above-mentioned step of determining the second internal resistance value of the target vehicle within the specified time period based on the identity information and the multiple first internal resistance values ​​obtained can be specifically operated in the following manner: according to the identity information of the target vehicle, determine the first internal resistance value of the battery to be tested corresponding to the target vehicle during each charging process within the specified time period; based on all the determined first internal resistance values, calculate the average value of all the first internal resistance values; this average value is similar to the average value mentioned in the above content, and will not be described in detail; the calculated average value is determined as the second internal resistance value of the battery to be tested within the specified time period. For example, an electric vehicle equipped with a battery pack undergoes three charging processes within seven days. The first internal resistance value of the electric vehicle during each charging process within these seven days is calculated respectively to obtain three first internal resistance values. Then, the arithmetic average of these three first internal resistance values ​​is calculated, and the arithmetic average is determined as the second internal resistance value of the electric vehicle within these seven days.

[0057] In actual application, the target vehicle may be a vehicle of the target model within the designated charging area within the designated time period. To facilitate identification of the source of the data sample, the data sample may also include regional information of the designated charging area and model information of the target model. The specific content of the regional information may include, but is not limited to, the postal code and city name of the designated charging area. The specific content of the model information may include, but is not limited to, the model number and manufacturer name. Based on this, in the case where there are multiple target vehicles within the designated charging area within the designated time period, the method may further include the following operations: obtaining the second internal resistance values ​​of all target vehicles within the designated charging area; and determining the third internal resistance value of the target model within the designated charging area within the designated time period based on the regional information, the model information, and the multiple obtained second internal resistance values.

[0058] As a feasible implementation method, the above-mentioned step of determining the third internal resistance value of the target vehicle model in the designated charging area within the designated time period based on the area information, the vehicle model information and the multiple second internal resistance values ​​obtained can be specifically operated in the following manner: based on the area information and the vehicle model information of the target vehicle model, determine the second internal resistance value of each target vehicle in the designated charging area within the designated time period; based on all the determined second internal resistance values, calculate the average value of these second internal resistance values; this average value is similar to the average value mentioned in the above content and will not be repeated here; the calculated average value is determined as the third internal resistance value of the target vehicle model in the designated charging area within the designated time period. For example, in order to know the third internal resistance value of a certain vehicle model in a certain city within seven days, the second internal resistance value of each electric vehicle of the same vehicle model in the city within these seven days is calculated respectively to obtain multiple second internal resistance values, and then the arithmetic average of these second internal resistance values ​​is calculated, and the arithmetic average is determined as the third internal resistance value of the same vehicle model in the city within these seven days.

[0059] On the basis of the above-mentioned method for determining the battery internal resistance, in order to further determine whether the second internal resistance value of a target vehicle within the specified time period is abnormal, the above-mentioned method may also include the following operation mode: calculating the discrete degree parameter of all the acquired second internal resistance values; and judging whether the second internal resistance value of each target vehicle is abnormal based on the above-mentioned third internal resistance value and the discrete degree parameter.

[0060] The above-mentioned discreteness parameter can be a standard deviation, variance, etc., and is not limited to this. As a feasible implementation method, the standard deviation of all the second internal resistance values ​​obtained is calculated, and the standard deviation is multiplied by three and then added to the above-mentioned third internal resistance value to obtain an internal resistance threshold. If the second internal resistance value of a target vehicle in the designated charging area exceeds the internal resistance threshold within the designated time period, it can be determined that the second internal resistance value of the target vehicle is abnormal. In actual application, as a possible implementation method, the above-mentioned internal resistance threshold can be defined according to the distribution of the second internal resistance value. For example, if the calculated second internal resistance value obeys a normal distribution, the above-mentioned internal resistance threshold can be defined as the mean of the normal distribution + 3×the standard deviation of the normal distribution, wherein the mean of the normal distribution is the above-mentioned third internal resistance, and the standard deviation of the normal distribution is the standard deviation of all the second internal resistance values ​​obtained above.

[0061] Based on the above method embodiment, the present application embodiment also provides a device for determining the internal resistance of a battery, see Figure 2 As shown, the device includes:

[0062] The data acquisition module 21 is used to obtain an initial data sample set of a single charging process of the battery under test within a specified time period; wherein the initial data sample set includes data samples at multiple different charging moments; wherein the data samples include at least the charging moment, SOC value, current value and voltage value.

[0063] The data cleaning module 22 is configured to clean the initial data sample set according to preset rules to obtain a first sample pair set comprising a plurality of first sample pairs; wherein each first sample pair is composed of two data samples with adjacent charging times in the initial data sample set.

[0064] The first internal resistance value determining module 23 is configured to determine a first internal resistance value of the battery under test during a single charging process within the specified time period according to the first sample pair set.

[0065] The above-mentioned battery internal resistance determination device provided in an embodiment of the present application, after obtaining battery parameter data samples of the battery during a single charging process within a period of time, will perform data cleaning on these data samples according to specific rules, thereby obtaining multiple sample pairs consisting of two data samples adjacent to each other at the charging moment, and finally determining the internal resistance value of the battery during a single charging process within this period of time based on these sample pairs. This operation method only requires simple data processing of the charging data of the battery within a period of time to obtain the internal resistance of the battery during this period. Compared with the method of directly measuring the battery internal resistance through an external device, it can reduce the cost required to determine the battery internal resistance. In addition, this operation method fully considers the real-time changes of the battery parameters during the charging process when determining the battery internal resistance, thereby improving the accuracy of the battery internal resistance determination result.

[0066] The above-mentioned data cleaning module 22 is also used to: form a first initial sample pair from two data samples with adjacent charging times in the initial data sample set to obtain a first initial sample pair set containing multiple first initial sample pairs; calculate the charging time interval, current difference and voltage difference of each first initial sample pair based on the charging time, current value and voltage value of the two data samples in each first initial sample pair; and take the first initial sample pair in the first initial sample pair set that meets the first preset condition as the first sample pair to obtain a first sample pair set.

[0067] The first internal resistance value determination module 23 is further configured to: calculate the first instantaneous internal resistance of each first sample pair in the first sample pair set based on the voltage difference and the current difference of each first sample pair; and determine the first internal resistance value of the battery under test during a single charge within the specified time period based on all the calculated first instantaneous internal resistances.

[0068] The first internal resistance value determining module 23 is further configured to: calculate an average value of all first instantaneous internal resistances based on all calculated first instantaneous internal resistances; and determine the calculated average value as the first internal resistance value of the battery under test during a single charge within the specified time period.

[0069] The battery to be tested is suitable for the target vehicle; the data sample also includes the identity information of the target vehicle; the battery to be tested has been charged multiple times within a specified time period; based on this, Figure 2 Based on the battery internal resistance determination device shown, the present application embodiment also provides another battery internal resistance determination device, see Figure 3 As shown, the device also includes:

[0070] The first internal resistance value obtaining module 24 is configured to obtain a first internal resistance value of the battery under test during each charging process within the specified time period.

[0071] The second internal resistance value determining module 25 is configured to determine a second internal resistance value of the target vehicle within the specified time period according to the identity information and the acquired multiple first internal resistance values.

[0072] The target vehicle is a vehicle of the target model within the specified time period in the specified charging area; there are multiple target vehicles in the specified charging area; the data sample also includes the area information of the specified charging area and the model information of the target model; based on this, Figure 3 Based on the battery internal resistance determination device shown, the present application embodiment also provides another battery internal resistance determination device, see Figure 4 As shown, the device also includes:

[0073] The second internal resistance value obtaining module 26 is configured to obtain the second internal resistance values ​​of all target vehicles in the designated charging area.

[0074] The third internal resistance value determining module 27 is configured to determine a third internal resistance value of the target vehicle type in the designated charging area within the designated time period according to the area information, the vehicle type information and the acquired multiple second internal resistance values.

[0075] The abnormality judgment module 28 is configured to calculate a discrete degree parameter of all acquired second internal resistance values; and judge whether the second internal resistance value of each target vehicle is abnormal based on the third internal resistance value and the discrete degree parameter.

[0076] The device for determining the internal resistance of a battery provided in the embodiment of the present application has the same implementation principle and technical effects as those of the aforementioned method embodiment. For the sake of brief description, for matters not mentioned in the device embodiment, reference may be made to the corresponding content in the aforementioned method embodiment.

[0077] The present application also provides an electronic device, such as Figure 5 As shown, it is a structural diagram of the electronic device, wherein the electronic device includes a processor 51 and a memory 50, the memory 50 stores computer executable instructions that can be executed by the processor 51, and the processor 51 executes the computer executable instructions to implement the above-mentioned method for determining the internal resistance of the battery.

[0078] exist Figure 5 In the illustrated embodiment, the electronic device further includes a bus 52 and a communication interface 53 , wherein the processor 51 , the communication interface 53 and the memory 50 are connected via the bus 52 .

[0079] Among them, the memory 50 may include a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 53 (which can be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. can be used. The bus 52 can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The bus 52 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0080] The processor 51 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the battery internal resistance determination method described above may be performed by hardware integrated logic circuits or software instructions within the processor 51. The processor 51 described above may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the battery internal resistance determination method disclosed in the embodiments of the present application may be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules within the decoding processor. The software module may be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or the like. The storage medium is located in the memory 50 , and the processor 51 reads the information in the memory 50 and completes the steps of the method for determining the internal resistance of the battery in the aforementioned embodiment in combination with its hardware.

[0081] An embodiment of the present application also provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions prompt the processor to implement the above-mentioned method for determining the internal resistance of the battery. The specific implementation can be found in the aforementioned method embodiment, which will not be repeated here.

[0082] The computer program product of the method, device, and electronic device for determining the internal resistance of a battery provided in the embodiments of the present application includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the method for determining the internal resistance of the battery described in the previous method embodiment. For specific implementation, please refer to the method embodiment and will not be repeated here.

[0083] Unless otherwise specifically stated, the relative steps, numerical expressions and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0084] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0085] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0086] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The scope of protection of the present application is not limited thereto. Although the present application has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed in the present application, or perform equivalent replacements for some of the technical features thereof. These modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the scope of protection of the claims.

Claims

1. A method for determining the internal resistance of a battery, characterized in that: The method comprises: Acquire an initial data sample set of a single charge process of the battery under test within a specified time period; wherein each data sample in the initial data sample set includes at least a charging time, a SOC value, a current value, and a voltage value; Cleaning the initial data sample set according to a preset rule to obtain a first sample pair set comprising a plurality of first sample pairs; wherein each first sample pair is composed of two data samples in the initial data sample set at adjacent charging times; determining a first internal resistance value of the battery to be tested during a single charging process within the specified time period according to the first sample pair set; The step of performing data cleaning on the initial data sample set according to a preset rule to obtain a first sample pair set including a plurality of first sample pairs includes: forming a first initial sample pair from two data samples with adjacent charging moments in the initial data sample set to obtain a first initial sample pair set including a plurality of first initial sample pairs; calculating a charging moment interval, a current difference, and a voltage difference of each first initial sample pair based on the charging moments, current values, and voltage values ​​of the two data samples in each first initial sample pair; and taking a first initial sample pair in the first initial sample pair set that meets a first preset condition as the first sample pair to obtain the first sample pair set; The first preset condition is satisfied as follows: the interval between the charging moments is no more than 30 seconds; the SOC values ​​of the two data samples in the same first initial sample pair are less than 80%; the current value of the latter charging moment in the same first initial sample pair is less than 10A; the current difference is within the range of 10A to 100A; and the voltage difference is within the range of 0V to 1V. The step of determining a first internal resistance value of the battery under test during a single charge within the specified time period based on the first sample pair set includes: calculating a first instantaneous internal resistance of each first sample pair based on a voltage difference and a current difference of each first sample pair in the first sample pair set; calculating an average value of all the calculated first instantaneous internal resistances based on all the calculated first instantaneous internal resistances; and determining the average value of all the calculated first instantaneous internal resistances as the first internal resistance value of the battery under test during a single charge within the specified time period; The battery to be tested is suitable for a target vehicle; the data sample also includes identity information of the target vehicle; the battery to be tested has undergone multiple charging processes within a specified time period; the method further includes: obtaining a first internal resistance value of the battery to be tested during each charging process within the specified time period; determining, based on the identity information, a first internal resistance value of the battery to be tested corresponding to the target vehicle during each charging process within the specified time period; calculating an average value of all the determined first internal resistance values ​​based on all the determined first internal resistance values; and determining the average value of all the calculated first internal resistance values ​​as a second internal resistance value of the target vehicle within the specified time period; The target vehicle is a vehicle of a target model within the specified time period in the designated charging area; there are multiple target vehicles within the specified time period in the designated charging area; the data sample also includes the area information of the designated charging area and the model information of the target model; the method also includes: obtaining the second internal resistance value of all target vehicles in the designated charging area; determining the second internal resistance value of each target vehicle in the designated charging area within the specified time period based on the area information and the model information; calculating the average value of all the determined second internal resistance values ​​based on all the determined second internal resistance values; and determining the average value of all the calculated second internal resistance values ​​as the third internal resistance value of the target model in the designated charging area within the specified time period.

2. The method for determining the internal resistance of a battery according to claim 1, wherein: The method further comprises: Calculating discrete degree parameters of all acquired second internal resistance values; It is determined whether the second internal resistance value of each target vehicle is abnormal based on the third internal resistance value and the discrete degree parameter.

3. A device for determining the internal resistance of a battery, characterized in that: The device comprises: A data acquisition module, configured to acquire an initial data sample set of a single charge of the battery under test within a specified time period; wherein the initial data sample set includes data samples at multiple different charging moments; wherein the data samples include at least the charging moment, SOC value, current value, and voltage value; a data cleaning module, configured to clean the initial data sample set according to a preset rule to obtain a first sample pair set comprising a plurality of first sample pairs; wherein each first sample pair is composed of two data samples in the initial data sample set at adjacent charging times; a first internal resistance value determining module, configured to determine a first internal resistance value of the battery to be tested during a single charging process within the specified time period according to the first sample pair set; The data cleaning module is further configured to: form a first initial sample pair from two data samples with adjacent charging times in the initial data sample set, thereby obtaining a first initial sample pair set comprising a plurality of the first initial sample pairs; calculate the charging time interval, current difference, and voltage difference of each first initial sample pair based on the charging times, current values, and voltage values ​​of the two data samples in each first initial sample pair; and select the first initial sample pair in the first initial sample pair set that meets the first preset condition as the first sample pair to obtain a first sample pair set; The first preset condition is satisfied as follows: the interval between the charging moments is no more than 30 seconds; the SOC values ​​of the two data samples in the same first initial sample pair are less than 80%; the current value of the latter charging moment in the same first initial sample pair is less than 10A; the current difference is within the range of 10A to 100A; and the voltage difference is within the range of 0V to 1V. The battery to be tested is suitable for a target vehicle; the data sample also includes identity information of the target vehicle; the battery to be tested has been charged multiple times within a specified time period; and the device further includes: A first internal resistance value acquisition module is used to obtain a first internal resistance value of the battery under test during each charging process within the specified time period; a second internal resistance value determination module, configured to: determine, based on the identity information, a first internal resistance value of the battery under test corresponding to the target vehicle during each charging process within the specified time period; calculate, based on all the determined first internal resistance values, an average value of all the determined first internal resistance values; and determine the average value of all the calculated first internal resistance values ​​as the second internal resistance value of the target vehicle within the specified time period; The target vehicle is a vehicle of a target vehicle type within the designated charging area within the designated time period; there are multiple target vehicles within the designated charging area within the designated time period; the data sample also includes area information of the designated charging area and vehicle type information of the target vehicle type; the device also includes: A second internal resistance value acquisition module is used to obtain the second internal resistance values ​​of all target vehicles in the designated charging area; The third internal resistance value determination module is used to: determine the second internal resistance value of each target vehicle in the designated charging area within the designated time period based on the area information and the vehicle model information; calculate the average value of all the determined second internal resistance values ​​based on all the determined second internal resistance values; and determine the average value of all the calculated second internal resistance values ​​as the third internal resistance value of the target vehicle model in the designated charging area within the designated time period.

4. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the method for determining the internal resistance of a battery according to claim 1 or 2.

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