Battery direct current internal resistance detection method and device, electronic equipment and medium

Abstract

The embodiment of the invention provides a battery direct current internal resistance detection method and device, electronic equipment and a medium, and belongs to the technical field of battery detection. The method comprises the following steps: controlling a to-be-tested battery to discharge according to a preset discharge rate, and recording a reference discharge capacity value and a reference discharge voltage value; charging and discharging operation is circularly executed, the ith capacity retention ratio is calculated, and if the ith capacity retention ratio is smaller than a preset capacity retention ratio threshold value, the charging and discharging operation is stopped. Obtaining at least one target discharge capacity value which is the same as the reference discharge capacity value according to the plurality of initial discharge capacity values, and obtaining a target discharge voltage value corresponding to each target discharge capacity value from each initial discharge voltage value; and calculating the DC internal resistance value of the to-be-measured battery according to the at least one target discharge voltage value and the reference discharge voltage value. Through the provided scheme, real-time monitoring of the internal resistance of the battery can be realized.

Description

Technical Field

[0001] The present application relates to the technical field of battery detection, and in particular to a method, device, electronic equipment and medium for detecting the DC internal resistance of a battery. Background Art

[0002] With the widespread application of electric vehicles and energy storage systems, battery health status monitoring has become very important. The DC internal resistance of a battery is a key indicator for evaluating the health of a battery, which reflects the resistance characteristics inside the battery. At present, there are the following problems when monitoring the DC internal resistance of a battery: the existing measurement method needs to interrupt the working state of the battery during monitoring, and it is impossible to monitor the battery when it is working normally. Summary of the invention

[0003] In order to solve the above technical problems, the embodiments of the present application provide a method, device, electronic device and medium for detecting the DC internal resistance of a battery.

[0004] In a first aspect, an embodiment of the present application provides a method for detecting a DC internal resistance of a battery, the method comprising: controlling a battery to be tested to discharge according to a preset discharge rate, and recording a reference discharge capacity value and a reference discharge voltage value;

[0005] Cyclic charge and discharge operations are performed to obtain a first discharge capacity value corresponding to the first charge and discharge, obtain a second discharge capacity value corresponding to the i-th charge and discharge, calculate an i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stop the charge and discharge operations if the i-th capacity retention rate is less than a preset capacity retention rate threshold, where i≥2;

[0006] Recording a plurality of initial discharge capacity values ​​and a plurality of initial discharge voltage values ​​corresponding to each charge and discharge operation;

[0007] Acquire at least one target discharge capacity value having the same value as the reference discharge capacity value according to the plurality of initial discharge capacity values, and acquire a target discharge voltage value corresponding to each target discharge capacity value from each of the initial discharge voltage values;

[0008] The DC internal resistance value of the battery to be tested is calculated according to at least one of the target discharge voltage value and the reference discharge voltage value.

[0009] In one embodiment, the battery to be tested is controlled to be charged according to a first preset current value until the charging voltage value reaches a first preset voltage threshold;

[0010] Controlling the battery to be tested to charge according to a preset voltage value until the charging current value reaches a preset current threshold;

[0011] The battery to be tested is left standing for a first preset waiting time, and the battery to be tested is controlled to discharge according to a second preset current value until the discharge voltage value reaches a second preset voltage threshold, and the battery is left standing for a second preset waiting time.

[0012] In one implementation, a voltage difference between each of the target discharge voltage values ​​and the reference discharge voltage value is obtained, and a plurality of the DC internal resistance values ​​are calculated according to the voltage difference and the second preset current value.

[0013] In one implementation, the internal resistance variation trend of the battery to be tested is determined according to each of the DC internal resistance values.

[0014] In one embodiment, a value divided by the first discharge capacity value and the second discharge capacity value is obtained, and the value divided is used as the capacity retention rate.

[0015] In one embodiment, at least one target discharge capacity value having the same value as the reference discharge capacity value is extracted from the plurality of initial discharge capacity values ​​by using a query function.

[0016] In a second aspect, an embodiment of the present application provides a battery DC internal resistance detection device, the battery DC internal resistance detection device comprising:

[0017] A first recording module, used to control the battery to be tested to discharge according to a preset discharge rate, and record a reference discharge capacity value and a reference discharge voltage value;

[0018] A second recording module is used to control the battery to be tested to charge and discharge according to a preset charge and discharge step. If the number of times the battery to be tested completes charge and discharge reaches a preset number of charge and discharge cycles, an initial discharge capacity value and an initial discharge voltage value corresponding to each preset number of charge and discharge cycles are recorded. If the battery to be tested completes a preset charge and discharge step, it is determined that the battery to be tested has completed an additional preset number of charge and discharge cycles.

[0019] an acquisition module, configured to extract a plurality of the initial discharge capacity values ​​having the same value as the reference discharge capacity value through a preset function, and to acquire each target discharge voltage value corresponding to each initial discharge capacity value from each of the initial discharge voltage values;

[0020] The obtaining module is used to obtain the DC internal resistance value of the battery to be tested according to the target discharge voltage value and the reference discharge voltage value.

[0021] In one embodiment, the first control module is used to control the battery to be tested to be charged according to a first preset current value until the charging voltage value reaches a first preset voltage threshold;

[0022] A second control module, used for controlling the battery to be tested to be charged according to a preset voltage value until the charging current value reaches a preset current threshold;

[0023] The static module is used to stand for a first preset waiting time, control the battery to be tested to discharge according to a second preset current value, until the discharge voltage value reaches a second preset voltage threshold, and stand for a second preset waiting time.

[0024] In a third aspect, an embodiment of the present application provides an electronic device, including a memory and a processor, wherein the memory is used to store a computer program, and when the computer program is run by the processor, the method for detecting the DC internal resistance of a battery provided in the first aspect is executed.

[0025] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium storing a computer program, which, when executed on a processor, executes the method for detecting the DC internal resistance of a battery provided in the first aspect.

[0026] The above-mentioned method for detecting the DC internal resistance of a battery provided by the present application includes: controlling the battery to be tested to discharge according to a preset discharge rate, and recording a reference discharge capacity value and a reference discharge voltage value; performing charge and discharge operations cyclically, obtaining a first discharge capacity value corresponding to the first charge and discharge, obtaining a second discharge capacity value corresponding to the i-th charge and discharge, calculating the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stopping the charge and discharge operation if the i-th capacity retention rate is less than a preset capacity retention rate threshold, wherein i≥2. Recording multiple initial discharge capacity values ​​and multiple initial discharge voltage values ​​corresponding to each charge and discharge operation, obtaining at least one target discharge capacity value having the same value as the reference discharge capacity value according to the multiple initial discharge capacity values, and obtaining a target discharge voltage value corresponding to each target discharge capacity value from each initial discharge voltage value; calculating the DC internal resistance value of the battery to be tested according to at least one target discharge voltage value and the reference discharge voltage value. By real-time monitoring of the battery internal resistance during normal charge and discharge of the battery, possible faults inside the battery can be discovered in a timely manner, thereby improving the efficiency and reliability of the battery development process. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and should not be regarded as limiting the scope of protection of the present application. In each of the drawings, similar components are numbered similarly.

[0028] Figure 1 A schematic diagram of a process of detecting a DC internal resistance of a battery provided in an embodiment of the present application is shown;

[0029] Figure 2 A schematic diagram of a battery capacity retention rate curve provided in an embodiment of the present application is shown;

[0030] Figure 3 A schematic diagram of a discharge capacity voltage curve provided in an embodiment of the present application is shown;

[0031] Figure 4 A schematic diagram of a DC internal resistance trend provided by an embodiment of the present application is shown;

[0032] Figure 5 A schematic diagram of the structure of a battery DC internal resistance detection device provided in an embodiment of the present application is shown;

[0033] Figure 6 A structural schematic diagram of an electronic device provided in an embodiment of the present application is shown.

[0034] Icons: 500 - detection device for battery DC internal resistance, 501 - first recording module, 502 - execution module, 503 - second recording module, 504 - acquisition module, 505 - calculation module, 506 - first control module, 507 - second control module, 508 - static module, 600 - electronic device, 601 - transceiver, 602 - processor, 603 - memory. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0036] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0037] Hereinafter, the terms "including", "having" and their cognates, which may be used in various embodiments of the present application, are intended only to indicate specific features, numbers, steps, operations, elements, components, or combinations of the foregoing items, and should not be understood as first excluding the existence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing items or adding the possibility of one or more features, numbers, steps, operations, elements, components, or combinations of the foregoing items.

[0038] Furthermore, the terms “first”, “second”, “third”, etc. are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0039] Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meanings as those generally understood by those skilled in the art to which the various embodiments of the present application belong. The terms (such as those defined in generally used dictionaries) will be interpreted as having the same meanings as the contextual meanings in the relevant technical field and will not be interpreted as having idealized meanings or overly formal meanings unless clearly defined in the various embodiments of the present application.

[0040] Example 1

[0041] An embodiment of the present application provides a method for detecting the DC internal resistance of a battery.

[0042] See also Figure 1 , the detection methods of battery DC internal resistance include:

[0043] S101, controlling the battery to be tested to discharge according to a preset discharge rate, and recording a reference discharge capacity value and a reference discharge voltage value.

[0044] In this embodiment, the battery to be tested is controlled to discharge at 0.05C. In other embodiments, other low-rate discharge rates may be selected, and power values ​​of 0.05C and below are usually used as low-rate discharge rates. It should be noted that a higher discharge rate will result in greater polarization, which may affect the subsequent calculation of the DC internal resistance of the battery. The voltage curve obtained at a lower discharge rate is closer to the open circuit voltage of the battery, so the reference discharge capacity value and reference discharge voltage value obtained are more reliable.

[0045] S102, cyclically performing charge and discharge operations, obtaining a first discharge capacity value corresponding to the first charge and discharge, obtaining a second discharge capacity value corresponding to the i-th charge and discharge, calculating the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stopping the charge and discharge operation if the i-th capacity retention rate is less than a preset capacity retention rate threshold, where i≥2.

[0046] It should be noted that the criterion for the end of the cycle is determined according to the design purpose. In other embodiments, the condition for the end of the cycle can be determined by the preset number of cycles. In this embodiment, the preset capacity retention rate threshold is 80%. When the capacity retention rate is less than the preset capacity retention rate threshold, the cycle is ended. In other embodiments, the preset capacity retention rate threshold can be set to other values. Here, this application does not limit the condition for the end of the cycle and the preset capacity retention rate threshold.

[0047] In one embodiment, a value divided by the first discharge capacity value and the second discharge capacity value is obtained, and the value divided is used as the capacity retention rate.

[0048] It is further explained that the capacity retention rate is obtained by dividing the second discharge capacity value corresponding to the i-th charge and discharge by the first discharge capacity value corresponding to the first charge and discharge, that is, the discharge capacity of the i-th cycle / the discharge capacity of the first cycle.

[0049] In this embodiment, if Figure 2 As shown in the figure, a nominal 100Ah lithium iron phosphate square battery is subjected to 1C charge and discharge aging at an ambient temperature of 25°C, and the battery is cycled for more than 3,000 cycles to obtain a capacity retention rate change curve. The discharge capacity voltage curve is obtained by cycling multiple times, as shown in the figure. Figure 3 shown.

[0050] This application obtains the capacity retention rate by performing cycle aging detection, and more intuitively understands the performance changes of the battery after multiple charge and discharge cycles, thereby providing data support for improving battery performance.

[0051] In one embodiment, the battery to be tested is controlled to be charged according to a first preset current value until the charging voltage value reaches a first preset voltage threshold; the battery to be tested is controlled to be charged according to a preset voltage value until the charging current value reaches a preset current threshold; the battery to be tested is left standing for a first preset waiting time, the battery to be tested is controlled to be discharged according to a second preset current value until the discharge voltage value reaches a second preset voltage threshold, and the battery to be tested is left standing for a second preset waiting time.

[0052] It should be noted that the first preset current value, the first preset voltage threshold, the preset voltage value, the preset current threshold, the first preset waiting time, the second preset current value, the second preset voltage threshold and the second preset waiting time can be set according to actual conditions.

[0053] In this embodiment, the specific charging and discharging steps are as follows: use 100A constant current charging to charge the battery under test, and stop charging when the cut-off voltage reaches 3.65V; use 3.65V constant voltage charging, and stop charging when the cut-off current reaches 5A; let it stand for 1800S; use 100A constant current discharge, and stop charging when the cut-off voltage reaches 2.5V; let it stand for 1800S. Each time a charging and discharging step is completed, the number of charge and discharge cycles is increased.

[0054] The present application estimates the DC internal resistance by using the discharge capacity value and discharge voltage value at different discharge rates, which will not interfere with the normal operation of the battery, maintains the consistency and reliability of the battery, and does not require the battery to be removed from the test environment, thereby reducing manual intervention and equipment costs.

[0055] S103, recording a plurality of initial discharge capacity values ​​and a plurality of initial discharge voltage values ​​corresponding to each charge and discharge operation.

[0056] It should be noted that by recording the initial discharge capacity value and the initial discharge voltage value after each charge and discharge operation, a data basis is provided for the subsequent calculation of the DC internal resistance.

[0057] S104, acquiring at least one target discharge capacity value having the same value as the reference discharge capacity value according to the plurality of initial discharge capacity values, and acquiring a target discharge voltage value corresponding to each target discharge capacity value from each of the initial discharge voltage values.

[0058] In one embodiment, at least one target discharge capacity value having the same value as the reference discharge capacity value is extracted from the plurality of initial discharge capacity values ​​by using a query function.

[0059] In the embodiment of the present application, the target discharge capacity value that is the same as the reference discharge capacity value is extracted by the VLOOKUP function. In other embodiments, the recorded discharge capacity value may be extracted by other query functions, which are not limited here.

[0060] S105, calculating a DC internal resistance value of the battery to be tested according to at least one of the target discharge voltage value and the reference discharge voltage value.

[0061] It should be noted that, by extracting a target discharge capacity value that is the same as the reference discharge capacity value, determining a target discharge voltage value according to the target discharge capacity value, obtaining a difference between the target discharge voltage value and the reference voltage value, and obtaining a division value of the difference with a second preset current value for discharge, the DC internal resistance value is calculated, and the specific formula is as follows:

[0062]

[0063] Among them, R is the DC internal resistance value, V0 is the reference discharge voltage value, V n is the target discharge voltage value, and I is the second preset current value.

[0064] This application provides a simple and effective method to process battery charge and discharge data, by finding the reference discharge voltage and subtracting it from the target discharge voltage, and then dividing it by the discharge current to get an approximate value of the DC internal resistance. This method avoids complex mathematical models and advanced algorithms, and is easy to implement and maintain.

[0065] In one implementation, a voltage difference between each of the target discharge voltage values ​​and the reference discharge voltage value is obtained, and a plurality of the DC internal resistance values ​​are calculated according to the voltage difference and the second preset current value.

[0066] It should be noted that the second preset current value is a discharge current value in the cyclic charge and discharge step, and the DC internal resistance value is calculated by obtaining the discharge current value and the voltage difference.

[0067] In one implementation, the internal resistance variation trend of the battery to be tested is determined according to each of the DC internal resistance values.

[0068] In the embodiment of the present application, a nominal 100Ah lithium iron phosphate square battery is used for 1C charge and discharge aging at an ambient temperature of 25°C, wherein the battery is cycled for more than 3000 times, and the DC internal resistance of different cycle numbers is obtained. The change trend of the DC internal resistance is as follows: Figure 4 shown.

[0069] The present application can output the DC internal resistance value in real time without the need for additional data processing steps, thereby improving the real-time and convenience of monitoring.

[0070] The method for detecting the DC internal resistance of a battery provided in this embodiment controls the battery to be tested to discharge according to a preset discharge rate, and records a reference discharge capacity value and a reference discharge voltage value; performs charge and discharge operations cyclically, obtains a first discharge capacity value corresponding to the first charge and discharge, obtains a second discharge capacity value corresponding to the i-th charge and discharge, calculates the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stops the charge and discharge operation if the i-th capacity retention rate is less than a preset capacity retention rate threshold, where i≥2. Record multiple initial discharge capacity values ​​and multiple initial discharge voltage values ​​corresponding to each charge and discharge operation, obtain at least one target discharge capacity value having the same value as the reference discharge capacity value according to the multiple initial discharge capacity values, and obtain a target discharge voltage value corresponding to each target discharge capacity value from each initial discharge voltage value; calculates the DC internal resistance value of the battery to be tested according to at least one target discharge voltage value and the reference discharge voltage value. By real-time monitoring of the battery internal resistance during normal charge and discharge of the battery, possible faults inside the battery can be discovered in a timely manner, thereby improving the efficiency and reliability of the battery development process.

[0071] Example 2

[0072] In addition, an embodiment of the present application provides a device for detecting the DC internal resistance of a battery.

[0073] like Figure 5 As shown, the battery DC internal resistance detection device 500 includes:

[0074] The first recording module 501 is used to control the battery to be tested to discharge according to a preset discharge rate, and record a reference discharge capacity value and a reference discharge voltage value;

[0075] An execution module 502 is used to cyclically execute the charge and discharge operation, obtain a first discharge capacity value corresponding to the first charge and discharge, obtain a second discharge capacity value corresponding to the i-th charge and discharge, calculate the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stop the charge and discharge operation if the i-th capacity retention rate is less than a preset capacity retention rate threshold, where i≥2;

[0076] The second recording module 503 is used to record a plurality of initial discharge capacity values ​​and a plurality of initial discharge voltage values ​​corresponding to each charge and discharge operation;

[0077] an acquisition module 504, configured to acquire at least one target discharge capacity value having the same value as the reference discharge capacity value according to the plurality of initial discharge capacity values, and to acquire a target discharge voltage value corresponding to each target discharge capacity value from each of the initial discharge voltage values;

[0078] The calculation module 505 is used to calculate the DC internal resistance value of the battery to be tested according to at least one of the target discharge voltage value and the reference discharge voltage value.

[0079] In one embodiment, the first control module 506 is used to control the battery to be tested to be charged according to a first preset current value until the charging voltage value reaches a first preset voltage threshold;

[0080] The second control module 507 is used to control the battery to be tested to be charged according to a preset voltage value until the charging current value reaches a preset current threshold;

[0081] The standstill module 508 is used to stand for a first preset waiting time, control the battery to be tested to discharge according to a second preset current value, until the discharge voltage value reaches a second preset voltage threshold, and stand for a second preset waiting time.

[0082] The battery DC internal resistance detection device 500 provided in this embodiment can implement the battery DC internal resistance detection method provided in Embodiment 1, which will not be described again to avoid repetition.

[0083] The battery DC internal resistance detection device provided in this embodiment can timely detect possible faults inside the battery by real-time monitoring the battery internal resistance during normal charging and discharging of the battery, thereby improving the efficiency and reliability of the battery development process.

[0084] Example 3

[0085] In addition, an embodiment of the present application provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program runs on the processor, the method for detecting the DC internal resistance of a battery provided in Example 1 is executed.

[0086] For details, see Figure 6 The electronic device 600 includes: a transceiver 601, a bus interface and a processor 602, wherein the processor 602 is used to: control the battery to be tested to discharge according to a preset discharge rate, and record a reference discharge capacity value and a reference discharge voltage value; cyclically perform the charge and discharge operation, obtain a first discharge capacity value corresponding to the first charge and discharge, obtain a second discharge capacity value corresponding to the i-th charge and discharge, calculate the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stop the charge and discharge operation if the i-th capacity retention rate is less than a preset capacity retention rate threshold, where i≥2; record multiple initial discharge capacity values ​​and multiple initial discharge voltage values ​​corresponding to each charge and discharge operation; obtain at least one target discharge capacity value having the same value as the reference discharge capacity value according to the multiple initial discharge capacity values, and obtain a target discharge voltage value corresponding to each target discharge capacity value from each initial discharge voltage value; calculate the DC internal resistance value of the battery to be tested according to at least one target discharge voltage value and the reference discharge voltage value.

[0087] In one embodiment, the processor 602 is also used to: control the battery to be tested to charge according to a first preset current value until the charging voltage value reaches a first preset voltage threshold; control the battery to be tested to charge according to a preset voltage value until the charging current value reaches a preset current threshold; stand still for a first preset waiting time, control the battery to be tested to discharge according to a second preset current value until the discharge voltage value reaches a second preset voltage threshold, and stand still for a second preset waiting time.

[0088] In one embodiment, the processor 602 is further configured to: obtain a voltage difference between each of the target discharge voltage values ​​and the reference discharge voltage value, and calculate a plurality of the DC internal resistance values ​​according to the voltage difference and the second preset current value.

[0089] In one implementation, the processor 602 is further configured to: determine a variation trend of the internal resistance of the battery to be tested according to each of the DC internal resistance values.

[0090] In one implementation, the processor 602 is further configured to: obtain a division value between the first discharge capacity value and the second discharge capacity value, and use the division value as the capacity retention rate.

[0091] In one implementation, the processor 602 is further configured to: extract at least one target discharge capacity value having the same value as the reference discharge capacity value from the plurality of initial discharge capacity values ​​through a query function.

[0092] In the embodiment of the present application, the electronic device 600 further includes a memory 603. Figure 6In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically linking various circuits of one or more processors represented by processor 602 and memory represented by memory 603. The bus architecture may also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 601 may be a plurality of components, i.e., including a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium. The processor 602 is responsible for managing the bus architecture and general processing, and the memory 603 may store data used by the processor 602 when performing operations.

[0093] The electronic device 600 provided in the embodiment of the present application can execute the steps of the method for detecting the DC internal resistance of the battery provided in the above method embodiment 1, which will not be described again to avoid repetition.

[0094] The electronic device provided in this embodiment can timely discover possible faults inside the battery by real-time monitoring the internal resistance of the battery during normal charging and discharging of the battery, thereby improving the efficiency and reliability of the battery development process.

[0095] Example 4

[0096] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method for detecting the DC internal resistance of a battery provided in Example 1 is implemented.

[0097] In this embodiment, the computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0098] The computer-readable storage medium provided in this embodiment can implement the method for detecting the DC internal resistance of the battery provided in Embodiment 1, and will not be described again here to avoid repetition.

[0099] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or terminal including the element.

[0100] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0101] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A method for detecting the DC internal resistance of a battery, characterized in that: The method comprises: Control the battery to be tested to discharge according to a preset discharge rate, and record a reference discharge capacity value and a reference discharge voltage value; Cyclic charge and discharge operations are performed to obtain a first discharge capacity value corresponding to the first charge and discharge, obtain a second discharge capacity value corresponding to the i-th charge and discharge, calculate an i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stop the charge and discharge operations if the i-th capacity retention rate is less than a preset capacity retention rate threshold, where i≥2; Recording a plurality of initial discharge capacity values ​​and a plurality of initial discharge voltage values ​​corresponding to each charge and discharge operation; Acquire at least one target discharge capacity value having the same value as the reference discharge capacity value according to the plurality of initial discharge capacity values, and acquire a target discharge voltage value corresponding to each target discharge capacity value from each of the initial discharge voltage values; The DC internal resistance value of the battery to be tested is calculated according to at least one of the target discharge voltage value and the reference discharge voltage value.

2. The method for detecting the DC internal resistance of a battery according to claim 1, characterized in that: Each charging and discharging operation includes: Controlling the battery to be tested to charge according to a first preset current value until the charging voltage value reaches a first preset voltage threshold; Controlling the battery to be tested to charge according to a preset voltage value until the charging current value reaches a preset current threshold; The battery to be tested is left standing for a first preset waiting time, and the battery to be tested is controlled to discharge according to a second preset current value until the discharge voltage value reaches a second preset voltage threshold, and the battery is left standing for a second preset waiting time.

3. The method for detecting the DC internal resistance of a battery according to claim 2, characterized in that: The step of obtaining the DC internal resistance value of the battery to be tested according to at least one of the target discharge voltage value and the reference discharge voltage value comprises: A voltage difference between each of the target discharge voltage values ​​and the reference discharge voltage value is obtained, and a plurality of the DC internal resistance values ​​are calculated according to the voltage difference and the second preset current value.

4. The method for detecting the DC internal resistance of a battery according to claim 3, characterized in that: The method further comprises: The internal resistance variation trend of the battery to be tested is determined according to each of the DC internal resistance values.

5. The method for detecting the DC internal resistance of a battery according to claim 1, characterized in that: The calculating the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value comprises: A value divided by the first discharge capacity value and the second discharge capacity value is obtained, and the value divided is used as the capacity retention rate.

6. The method for detecting the DC internal resistance of a battery according to claim 1, characterized in that: The step of obtaining at least one target discharge capacity having the same value as the reference discharge capacity value according to the plurality of initial discharge capacity values ​​comprises: At least one target discharge capacity value having the same value as the reference discharge capacity value is extracted from the plurality of initial discharge capacity values ​​by using a query function.

7. A battery DC internal resistance detection device, characterized in that: The device comprises: A first recording module, used to control the battery to be tested to discharge according to a preset discharge rate, and record a reference discharge capacity value and a reference discharge voltage value; an execution module, configured to cyclically execute the charge and discharge operation, obtain a first discharge capacity value corresponding to the first charge and discharge, obtain a second discharge capacity value corresponding to the i-th charge and discharge, calculate the i-th capacity retention rate according to the first discharge capacity value and the second discharge capacity value, and stop the charge and discharge operation if the i-th capacity retention rate is less than a preset capacity retention rate threshold, wherein i≥2; A second recording module records a plurality of initial discharge capacity values ​​and a plurality of initial discharge voltage values ​​corresponding to each charge and discharge operation; an acquisition module, configured to acquire at least one target discharge capacity value having the same value as the reference discharge capacity value according to the plurality of initial discharge capacity values, and to acquire a target discharge voltage value corresponding to each target discharge capacity value from each of the initial discharge voltage values; A calculation module is used to calculate the DC internal resistance value of the battery to be tested according to at least one of the target discharge voltage value and the reference discharge voltage value.

8. The battery DC internal resistance detection device according to claim 7, characterized in that: The device also includes: A first control module, used for controlling the battery to be tested to be charged according to a first preset current value until the charging voltage value reaches a first preset voltage threshold; A second control module, used for controlling the battery to be tested to be charged according to a preset voltage value until the charging current value reaches a preset current threshold; The static module is used to stand for a first preset waiting time, control the battery to be tested to discharge according to a second preset current value, until the discharge voltage value reaches a second preset voltage threshold, and stand for a second preset waiting time.

9. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program, and when the processor is running, the computer program executes the method for detecting the DC internal resistance of a battery according to any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: The computer program is stored therein, and when the computer program is run on a processor, the method for detecting the DC internal resistance of a battery according to any one of claims 1 to 6 is executed.

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