A dynamic EIS test method based on charge and discharge equipment and related equipment

Abstract

The application provides a dynamic EIS test method based on a charging and discharging device and related equipment, and relates to the technical field of electric digital data processing. The method comprises the following steps: firstly, a main channel constant current step is started by controlling the charging and discharging device, so that the battery reaches a stable charging and discharging state. After the battery meets the EIS starting condition, when it is confirmed that the non-main channel EIS is not started, a DEIS relay module built in the charging and discharging device is used for channel switching. After the channel switching is completed, the EIS module is controlled to inject a preset amplitude AC disturbance current into the battery, the voltage response signal of the battery is obtained, and impedance data containing impedance amplitude, phase and the like are calculated in real time, so that dynamic and accurate test of the electrochemical impedance spectrum of the battery is realized.

Description

Technical Field

[0001] The present application relates to the technical field of electrical digital data processing, and in particular to a dynamic EIS testing method based on charging and discharging equipment and related equipment. Background Art

[0002] In the field of battery performance testing, with the rapid development of new energy technologies, there is a growing demand for analyzing the characteristics of batteries under dynamic operating conditions. Electrochemical impedance spectroscopy (EIS), a testing method that can effectively reflect the internal electrochemical processes and interface characteristics of batteries, is of great value in battery research and development, production, and application scenarios.

[0003] Currently, traditional battery impedance testing is typically performed under static conditions, requiring the battery to be isolated from the charge and discharge circuits and kept at rest. This testing method relies on the independent operation of the charge and discharge equipment and the EIS test equipment, requiring manual intervention to switch the test circuits. This process is cumbersome and time-consuming.

[0004] The main problem with existing technologies is that static testing modes cannot meet the real-time impedance monitoring requirements of batteries during their charge and discharge states in actual applications. During the charge and discharge process, the battery's internal chemical reaction rates, ion diffusion paths, and interface states are all in dynamic change. Traditional testing methods are unable to inject AC disturbances and collect response signals in real time during the charge and discharge process, resulting in an inability to obtain impedance data that reflects the battery's dynamic characteristics. This makes it difficult to accurately assess the battery's performance and health status in actual operating scenarios, hindering in-depth research and precise management of battery dynamic behavior. Summary of the Invention

[0005] The present application provides a dynamic EIS testing method and related equipment based on charging and discharging equipment, which is used to realize efficient and accurate electrochemical impedance spectroscopy (EIS) testing during the dynamic charging and discharging process of the battery.

[0006] In the first aspect, the present application provides a dynamic EIS testing method based on a charging and discharging device, which is applied to a host computer in a test system. The method includes: controlling the charging and discharging device to start the constant current step of the main channel to put the battery in a stable charging and discharging state; after determining that the battery meets the EIS start-up conditions, determining the EIS start-up state of the non-main channel; after determining that the EIS start-up state is an unstarted state, switching the channel through a DEIS relay module, which is built into the charging and discharging device; after confirming that the channel switching is completed, controlling the EIS module to continuously inject an AC disturbance current of a preset amplitude into the battery; obtaining a response voltage signal, and calculating impedance data in real time, which impedance data at least includes impedance amplitude and impedance phase.

[0007] By adopting the above technical solution, the charging and discharging equipment is first controlled to start the main channel constant current process to put the battery in a stable charging and discharging state, which provides a stable basic environment for subsequent EIS testing. Performing EIS testing in a stable state can reduce the impact of external interference factors on the test results. Then, after determining that the battery has met the EIS startup conditions, the non-main channel EIS startup state is determined to avoid interference with the test caused by the non-main channel EIS operation. After that, the channel is switched through the DEIS relay module, and the EIS module is connected to the main channel. This can accurately perform EIS testing on batteries in a stable state, so that the test results more accurately reflect the electrochemical characteristics of the battery, providing a reliable basis for battery performance evaluation and status monitoring.

[0008] In combination with some embodiments of the first aspect, in some embodiments, after the step of controlling the charging and discharging equipment to start the constant current step, it also includes: real-time monitoring of the battery status to obtain battery status information, which battery status information at least includes battery voltage information and battery charge status information; obtaining the duration of the constant current step; if the battery status information and the duration are greater than the set EIS start standard value, it is determined that the battery meets the EIS start condition.

[0009] By adopting the above technical solution, after controlling the charging and discharging equipment to initiate the constant current step, the battery status is monitored in real time and the duration of the constant current step is obtained. By combining the battery status information and the duration with the set EIS initiation standard value for comparison, it can accurately determine whether the battery has reached a state suitable for EIS testing. Battery voltage information and battery state of charge information directly reflect the current battery state, while the duration reflects the stability of the battery state. Only when both factors meet the standard values ​​is the battery determined to have met the EIS initiation conditions, ensuring that the EIS test is conducted when the battery state is stable and suitable, thereby improving the accuracy and reliability of the test results and avoiding test data deviations caused by unstable battery state.

[0010] In combination with some embodiments of the first aspect, in some embodiments, after the step of determining the EIS startup status of the non-master channel, it also includes: if the EIS startup status is the startup state, sending a queue waiting instruction to the DEIS relay module; if the EIS startup status is the non-startup state, sending an EIS startup instruction to the DEIS relay module.

[0011] By employing this technical solution, after determining the EIS startup status of a non-master channel, different instructions are taken based on the status. If the EIS startup status is enabled, a queue command is issued to prevent channel conflicts and data interference caused by multiple EIS tests running simultaneously, thus ensuring test order. If the EIS is not enabled, an EIS startup command is issued to initiate the test promptly, improving test efficiency. This dynamic adjustment based on status optimizes the multi-channel EIS testing process, avoids resource waste and test confusion, and enables the test system to operate in an orderly and efficient manner, ensuring that each EIS test is conducted at the appropriate time and improving overall test quality.

[0012] In combination with some embodiments of the first aspect, in some embodiments, the step of switching the channel through the DEIS relay module specifically includes: cutting off the connection of the non-main channel through the relay in the DEIS relay module, and connecting the EIS module in parallel to the main channel.

[0013] By employing this technical solution, when switching channels via the DEIS relay module, the non-primary channel is disconnected and the EIS module is connected in parallel to the primary channel. This allows EIS testing to be concentrated on the primary channel, preventing the electrical characteristics of the non-primary channel from affecting the primary channel test. Connecting EIS modules in parallel allows the AC disturbance current to be injected more directly into the battery, reducing losses and interference during signal transmission and improving the quality of the response voltage signal.

[0014] In combination with some embodiments of the first aspect, in some embodiments, after the step of obtaining the response voltage signal and calculating the impedance data in real time, it also includes: after confirming that the EIS step is completed, controlling the DEIS relay module to cut off the connection with the main channel, and restoring the connection of the non-main channel according to the initial channel connection state, and the initial channel connection state is the connection state of the non-main channel before the channel is switched through the DEIS relay module.

[0015] By implementing the above technical solution, after confirming the completion of the EIS step, the DEIS relay module is controlled to disconnect from the main channel and restore the connection to the non-main channel. Promptly disconnecting the EIS module prevents interference with the battery's subsequent charging and discharging processes, ensuring proper battery operation. Restoring the non-main channel connection according to the initial channel connection status returns the battery system to its pre-test state without affecting subsequent battery use or other testing. This orderly recovery operation ensures the stability and continuity of the battery system, while also preparing for the next EIS test or other operations, minimizing the impact of the entire testing process on the battery's normal operation.

[0016] In combination with some embodiments of the first aspect, in some embodiments, after confirming that the EIS work step is completed, controlling the DEIS relay module to cut off the connection with the main channel and restoring the connection of the non-main channel according to the initial channel connection state specifically includes: sending an instruction to the EIS module to stop injecting the AC disturbance current; after detecting the feedback signal that the AC disturbance current has returned to zero, waiting for a set time length so that the AC disturbance current completely stops being output; controlling the relay in the DEIS relay module to disconnect the main channel; detecting the voltage value at both ends of each non-main channel through the DEIS relay module, and calculating the channel difference between the voltage value and the main channel voltage; if the channel difference exceeds the set channel voltage difference threshold, skipping the corresponding channel and recording the abnormality, and not performing the connection recovery operation; if the channel difference does not exceed the set channel voltage difference threshold, performing the connection recovery operation.

[0017] By employing this technical solution, when restoring channel connections after confirming the completion of the EIS step, the AC disturbance current injection is first stopped and allowed to return to zero, ensuring that current output completely ceases and preventing residual current from affecting subsequent operations. The voltage values ​​of non-main channels are detected and compared with those of the main channel, calculating the channel difference. If the difference exceeds a threshold, the corresponding channel is skipped and the anomaly is recorded, preventing circuit failures and safety hazards caused by voltage mismatches. If the difference does not exceed the threshold, the connection is restored, ensuring the safety and reliability of the channel connection. This allows the battery system to be stably and safely restored to normal operation after testing, reducing the risk of system failure.

[0018] In combination with some embodiments of the first aspect, in some embodiments, after determining that the EIS startup state is the non-startup state, after the step of switching the channel through the DEIS relay module, it also includes: displaying the connectivity status of each channel through multiple LED lights, and the LED lights are set in each channel; obtaining the startup status of multiple LED lights; if the startup state is detected to be started, sending a channel switching fault reminder to the display end.

[0019] By implementing this technical solution, after channel switching, LEDs display the channel connectivity status and indicate its startup status. The LEDs provide a visual indicator of channel connectivity, allowing operators to easily understand channel status in real time. If an abnormal LED startup status is detected, a channel switching fault alert is issued, promptly identifying any issues during the channel switching process. Rapid fault detection enables operators to take timely remedial measures, minimizing the impact of the fault on testing and improving test efficiency and success rates. Furthermore, fault records provide a basis for subsequent system maintenance and improvements, contributing to enhanced reliability and stability of the entire test system.

[0020] In a second aspect, the present application provides a test system comprising: one or more processors and a memory; the memory is coupled to the one or more processors, the memory being used to store computer program code, the computer program code comprising computer instructions, the one or more processors calling the computer instructions to enable the test system to execute the method described in the first aspect and any possible implementation of the first aspect.

[0021] In a third aspect, the present application provides a computer-readable storage medium comprising instructions, which, when executed on a test system, causes the test system to execute the method described in the first aspect and any possible implementation of the first aspect.

[0022] In a fourth aspect, the present application provides a computer program product. When the computer program product is run on a test system, the test system executes the method described in the first aspect and any possible implementation of the first aspect.

[0023] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0024] 1. By adopting the technical means of switching channels through the DEIS relay module to perform EIS testing under stable charge and discharge conditions, the technical problem of EIS testing in the existing technology being easily affected by unstable battery conditions and channel interference is effectively solved, thereby achieving the technical effect of making the test results more accurately reflect the electrochemical characteristics of the battery and providing a reliable basis for battery performance evaluation and condition monitoring.

[0025] 2. By combining battery status information and the duration of the constant current step to determine the EIS start conditions, the technical problem of the existing technology that it is difficult to accurately determine whether a battery is suitable for EIS testing is effectively solved. This ensures that the test is carried out when the battery state is stable and suitable, and improves the accuracy and reliability of the test results.

[0026] 3. By adopting the technical means of detecting the channel voltage difference after stopping the injection of AC disturbance current and performing the connection recovery operation based on the threshold, the technical problem of voltage mismatch causing failure in the channel recovery after EIS test in the existing technology is effectively solved, thereby achieving the technical effect of ensuring the safety and reliability of channel connection and reducing the risk of system failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the overall framework of the dynamic EIS testing method based on the charging and discharging equipment in the embodiment of the present application;

[0028] Figure 2This is a flow chart of a dynamic EIS test method based on a charge-discharge device in an embodiment of the present application;

[0029] Figure 3 This is another flow chart of the dynamic EIS testing method based on the charging and discharging equipment in the embodiment of the present application;

[0030] Figure 4 It is a schematic diagram of the structure of a physical device of the test system in an embodiment of the present application. DETAILED DESCRIPTION

[0031] The terms used in the following examples of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. As used in the specification and appended claims of the present application, the singular expressions "a," "an," "said," "above," "the," and "this" are intended to include plural expressions as well, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present application refers to and encompasses any or all possible combinations of one or more of the listed items.

[0032] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of the technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of this application, unless otherwise specified, "plurality" means two or more.

[0033] For ease of understanding, the following is an overview of the method provided by this implementation. Figure 1 , which is a schematic diagram of the overall framework of the dynamic EIS testing method based on charging and discharging equipment in an embodiment of the present application.

[0034] Figure 1This article demonstrates the interconnection of the core components of a dynamic EIS test system based on a charging and discharging device. The overall framework is built around implementing dynamic EIS testing during battery charging and discharging. It primarily encompasses key components such as the host computer, slave computer, EIS module, DEIS relay module, and the charging and discharging device. These components work together via serial communication and specific circuit connections. Serial communication is used to exchange data between the host computer, slave computer, EIS module, and charging and discharging device. Commands from the host computer are forwarded by the slave computer to the EIS module and DEIS relay module to control the test process. Simultaneously, the slave computer and EIS module transmit test data back to the host computer. The DEIS relay module, built into the charging and discharging device, is responsible for channel switching. When the host computer initiates the EIS test, the DEIS relay module disconnects other channels and connects the EIS module to the main channel, ensuring accurate injection of test current into the battery cell. During the charging and discharging process, the EIS module injects AC perturbation current into the battery cell, collects the response voltage signal, and calculates impedance data. The host computer controls the charging and discharging equipment to initiate the constant current step in the main channel, allowing the battery to reach a stable charge and discharge state. Once the EIS startup conditions are met, the host computer controls the DEIS relay module to switch channels, and the EIS module then begins testing. After the test is completed, the DEIS relay module restores the channel's initial connection state to ensure normal operation of the charging and discharging equipment.

[0035] The following is a more detailed description of the process of this implementation. Figure 2 , which is a flow chart of a dynamic EIS testing method based on charging and discharging equipment in an embodiment of the present application.

[0036] S201, controlling the charging and discharging equipment to start the constant current step of the main channel to keep the battery in a stable charging and discharging state;

[0037] Among them, "charge and discharge equipment" refers to a device used to charge or discharge a battery. It can adjust current, voltage, and other parameters according to set parameters to achieve control of the battery's charge and discharge process. "Main channel" refers to the circuit channel in the charge and discharge equipment that is primarily used to connect the battery for charging and discharging. In multi-channel charge and discharge equipment, the main channel bears the primary charge and discharge tasks, and the connection with the battery is more direct and critical. "Constant current step" refers to a working stage in the charge and discharge process that maintains a constant current. By controlling the charge and discharge equipment to output a stable current, the battery is charged or discharged at a fixed current value, such as setting the battery to charge at a constant current of 1A.

[0038] This step is typically performed before a dynamic EIS test on a battery to create a stable environment for subsequent EIS testing. In practical applications, such as testing the performance of newly produced batteries on a battery production line or testing battery performance under different conditions during battery development, this step is essential. Specifically, the host computer first sends a start command to the charge / discharge device. This command specifies the main channel's constant current step and carries parameters such as the current value. Upon receiving the command, the charge / discharge device adjusts its internal circuitry based on the set parameters, ensuring that the main channel outputs a stable constant current, charging and discharging the connected battery. During this process, the host computer also monitors battery status information, such as voltage and temperature, in real time to ensure stable charging and discharging. If any abnormal battery status is detected, such as excessive voltage fluctuation or elevated temperature, the host computer promptly adjusts the charge / discharge device's parameters or stops the charge / discharge operation to ensure battery safety and test accuracy.

[0039] When implementing this step, the charging and discharging device may not accurately output the set constant current. This may be due to aging of internal circuit components, precision deviations, or external electromagnetic interference. To address this issue, a high-precision current detection circuit can be added between the charging and discharging device and the battery to monitor the actual output current in real time. The host computer compares the detected actual current value with the set current value. If the deviation between the two exceeds a certain range, the host computer sends an adjustment command to the charging and discharging device to adjust the output current. For example, if the set current value is 1A and the actual current is detected to be 0.95A, the host computer calculates the deviation to be 0.05A, which exceeds the allowable error range. It then sends a command to the host computer to increase the output current appropriately until the actual current approaches or reaches the set value.

[0040] After this step, the battery status can be monitored in real time to obtain battery status information, which includes at least battery voltage and state of charge (SOC). The duration of the constant current step is then determined. If the battery status information and duration exceed the set EIS triggering threshold, the battery is determined to have met the EIS triggering condition. "Battery status information" refers to a collection of real-time data on the battery's condition during the charge and discharge process. "Battery voltage information" refers to the potential difference between the positive and negative electrodes, reflecting the battery's current energy storage and release status. Specifically, after the host computer controls the charging and discharging equipment to initiate the main channel constant current step, it collects real-time battery voltage and SOC information via sensors connected to the battery. Simultaneously, a timer within the host computer begins recording the duration of the constant current step. During this collection and recording process, the host computer continuously compares the real-time battery status information and duration with the set EIS triggering threshold. If the battery voltage and state of charge are within the set range, and the duration of the constant current step also meets or exceeds the set standard, the host computer determines that the battery has met the EIS start conditions, and subsequent EIS test operations can be performed at this time; if any of these conditions are not met, the host computer continues to wait, continuously monitoring the battery status and constant current step duration until the standards are met.

[0041] S202: After determining that the battery meets the EIS start condition, determine the EIS start state of the non-primary channel;

[0042] "Battery" refers to the object undergoing charge-discharge operations and EIS testing; "EIS Start Conditions" describes the criteria used to determine whether an EIS test can be initiated; "Non-primary Channels" refer to channels other than the primary channel in a charge-discharge device, which may also be used for EIS testing or other functions in certain circumstances. "EIS Start Status" indicates whether the EIS test on a non-primary channel has been initiated, including either enabled or disabled.

[0043] This step is performed after the battery is in a stable charge and discharge state and meets the EIS start conditions. Its function is to avoid interference caused by EIS tests on multiple channels at the same time and to ensure the accuracy of the test results. For example, in a multi-channel battery testing system, each channel is connected to a different battery. When a dynamic EIS test is performed on one of the batteries, it is necessary to ensure that the EIS test status of other channels will not affect this test. Specifically, after the host computer determines that the battery has met the EIS start conditions, it will send an instruction to the charging and discharging device to obtain the EIS start status information of the non-main channel. After receiving the instruction, the charging and discharging device will query the EIS test-related identifiers or status registers of each non-main channel, and then feed this information back to the host computer. The host computer determines the EIS start status of each non-main channel based on the feedback information received. If there are multiple non-main channels, the host computer will judge and record them one by one.

[0044] After this step, if it is determined that the EIS startup status is the startup status, a queue waiting instruction is sent to the DEIS relay module; if the EIS startup status is the non-startup status, an EIS startup instruction is sent to the DEIS relay module. The "queue waiting instruction" is used to instruct the DEIS relay module to suspend the current channel switching operation and wait for other ongoing EIS tests to be completed, so as to avoid channel conflicts and data interference caused by multiple EIS tests being carried out at the same time. The "EIS startup instruction" is used to notify the DEIS relay module to start channel switching, connect the EIS module to the main channel, and prepare for subsequent EIS tests. This step is executed after determining the EIS startup status of the non-main channel. Its purpose is to optimize the multi-channel EIS test process and ensure that the test is carried out in an orderly and efficient manner. In a multi-channel battery test scenario, each channel may be connected to a different battery for EIS testing. If multiple channels start EIS testing at the same time, it may cause electrical interference, affect the accuracy of the test data, and even damage the test equipment. Specifically, after the host computer obtains the EIS startup status information of the non-main channel, it will judge the status. If it is detected that the EIS startup status of a non-main channel is in the startup state, it means that the EIS test of the channel is in progress. At this time, the host computer immediately sends a queue waiting instruction to the DEIS relay module. After receiving the instruction, the DEIS relay module will suspend the switching operation of the channel and put its switching task into the waiting queue until the ongoing EIS test is completed. If it is determined that the EIS startup status of the non-main channel is not started, it means that the channel is not currently undergoing EIS test and will not interfere with the upcoming test. The host computer will send an EIS startup instruction to the DEIS relay module. After receiving the instruction, the DEIS relay module will cut off the connection of other non-related channels according to the preset program, and connect the EIS module to the main channel to create conditions for the subsequent injection of AC disturbance current and EIS test.

[0045] S203, after determining that the EIS startup state is not started, switching the channel through the DEIS relay module, the DEIS relay module is built into the charging and discharging device;

[0046] A "DEIS relay module" is a relay combination module built into the charging and discharging equipment that implements channel switching. It consists of multiple relays that can disconnect or connect different circuit channels based on control signals, ensuring that the EIS module is connected to the main channel during EIS testing. "Channel switching" refers to changing the connection method of channels in a circuit. In this scenario, it involves switching the EIS module from a disconnected state to a connected main channel, while disconnecting other non-relevant channels to ensure that the EIS test is performed on the correct channel.

[0047] This step is performed after determining that the EIS activation status of the non-primary channel is not enabled. Its purpose is to accurately connect the EIS module to the primary channel, ensuring a smooth EIS test. During the battery test, when the EIS test conditions are met and the other non-primary channels are not undergoing EIS testing, a channel switch operation is required. Specifically, after confirming that the EIS activation status of the non-primary channel is not enabled, the host computer sends a channel switch command to the DEIS relay module in the charging and discharging equipment. After receiving the command, the DEIS relay module's internal control circuit controls the opening and closing states of each relay according to the command content. First, it disconnects all channels other than the non-primary channel that may affect the EIS test to prevent electrical interference from other channels. Then, the EIS module is connected in parallel to the primary channel, enabling the EIS module to establish an electrical connection with the battery and prepare for the subsequent injection of AC disturbance current into the battery. During the switching process, the host computer also monitors the operating status of the DEIS relay module in real time to ensure the successful completion of the switching operation. If any anomalies occur during the switching process, such as a relay failing to operate properly, the host computer will promptly issue an alarm and take appropriate measures.

[0048] The connectivity status of each channel can also be displayed through multiple LED lights, which are set in each channel; the startup status of multiple LED lights is obtained; if the startup status is detected to be startup, a channel switching fault reminder is sent to the display end. The "connectivity status of the channel" indicates whether the channel is in a normal connection and can transmit current. When the channel is normally connected, the corresponding LED light is on; otherwise, if the channel is not connected or there is a fault, the LED light is off. The "startup status of the LED light" refers to the current on and off status of the LED light. On means the startup status is on, and off means the startup status is off. The "display end" refers to the device used to display various types of information, such as a computer display screen, a control terminal screen, etc. The host computer sends a channel switching fault reminder to it so that the operator can obtain abnormal information in a timely manner.

[0049] This operation is performed after the DEIS relay module switches channels. It is primarily used to monitor channel connection status in real time during battery testing. During battery testing, channel switching is frequent, and channel connection status directly impacts the accuracy of test results and the safety of the testing process. Therefore, timely detection of any issues during channel switching is crucial. Specifically, after the DEIS relay module completes the channel switching operation, the LEDs within each channel illuminate or deactivate based on the channel's connectivity. The host computer receives the activation status information of the multiple LEDs through the circuit interface connected to the LEDs. This information is transmitted to the host computer in the form of digital signals. For example, a high level indicates that the LED is on (activation status), while a low level indicates that the LED is off. After receiving these signals, the host computer analyzes and interprets them. If one or more LEDs are detected as being activated (i.e., illuminated), but the host computer expects the channel to be disconnected (for example, during a specific test, a channel should be disconnected after switching), the host computer determines that a channel switching failure has occurred. At this point, the host computer will send a channel switching fault reminder message to the display terminal according to the pre-set communication protocol. The fault reminder message may include the channel number of the fault and the time of fault occurrence, so that the operator can quickly locate and solve the problem.

[0050] S204: After confirming that the channel switching is completed, controlling the EIS module to continuously inject an AC disturbance current of a preset amplitude into the battery;

[0051] This step is performed after confirming that the channel has been successfully switched. Its purpose is to obtain the battery's response to AC disturbances, thereby calculating the battery's impedance data and providing a basis for evaluating battery performance. Specifically, after receiving the feedback signal from the DEIS relay module indicating that the channel switching is complete, the host computer will immediately send a control instruction to the EIS module. This instruction clearly contains the AC disturbance current parameter information of the preset amplitude. After the EIS module receives the instruction, the internal signal generator starts working and generates an AC disturbance current that meets the preset amplitude requirements. This AC disturbance current will be continuously injected into the battery connected to the main channel. During the injection process, the host computer will also monitor the working status of the EIS module in real time to ensure that the current is injected stably and continuously. At the same time, the host computer will also monitor some basic battery conditions, such as voltage and temperature, to prevent adverse effects on the battery caused by the injected current. For example, if abnormal fluctuations in the battery voltage are found during the injection process, the host computer may suspend the injection operation and further evaluate the battery status.

[0052] S205 , acquiring a response voltage signal, and calculating impedance data in real time, where the impedance data at least includes an impedance amplitude and an impedance phase.

[0053] The "response voltage signal" represents the voltage response signal generated by the battery after being injected with an AC perturbation current. This signal contains information about the electrochemical processes within the battery, and analysis of it can reveal the battery's impedance characteristics. The "impedance data" describes the battery's resistance to the AC perturbation current. The impedance amplitude indicates the extent of the battery's resistance to the current, while the impedance phase reflects the phase difference between the voltage and current.

[0054] This step is performed immediately after the EIS module injects an AC perturbation current into the battery. Its primary purpose is to obtain battery impedance data, thereby assessing its performance and health. Specifically, when the EIS module injects the AC perturbation current into the battery, the battery generates a corresponding response voltage signal. The voltage acquisition circuit within the EIS module collects this response voltage signal in real time, converts it into a digital signal, and transmits it to the host computer. After receiving the voltage signal data, the host computer processes it according to a pre-programmed algorithm. First, mathematical methods such as the Fourier transform are used to convert the time-domain voltage signal into the frequency domain, obtaining voltage amplitude and phase information at different frequencies. Then, combining the frequency and amplitude of the injected AC perturbation current, the battery's impedance amplitude and phase at each frequency are calculated according to the complex form of Ohm's law (Z = V / I, where Z is impedance, V is voltage, and I is current). During the calculation process, the host computer also filters the data to remove noise and improve data accuracy. The calculated impedance data is then displayed in real time, allowing operators to quickly understand the battery's status. If abnormal changes in impedance data are found, the host computer may trigger an alarm, prompting the operator to conduct further inspection of the battery.

[0055] After confirming that the electrochemical impedance spectroscopy (EIS) test step has been completed, the DEIS relay module in the charging and discharging equipment needs to adjust and restore the channel connection status. Specifically, during the EIS test, the DEIS relay module will connect the main channel to the EIS module, and may also adjust the connection status of non-main channels to meet the test requirements. After the EIS test is completed, the host computer will first confirm whether the EIS step has indeed been completed. This can be achieved by detecting the test completion signal returned by the EIS module and checking whether the test data is complete.

[0056] Once the test is confirmed to be complete, the host computer controls the DEIS relay module to perform two key operations. First, it disconnects the main channel from the EIS module, restoring the main channel to its pre-EIS state and preventing the EIS module from affecting the subsequent normal charging and discharging operations of the main channel. Second, it restores the connection status of the non-main channel to its initial state. The "initial channel connection state" here refers to the original connection state of the non-main channel before the DEIS relay module switches the channel to conduct the EIS test.

[0057] To achieve this process, the host computer needs to operate according to specific logic. First, the host computer sends an instruction to the DEIS relay module through the communication interface to cut off the connection between the main channel and the EIS module. After receiving the instruction, the DEIS relay module drives the corresponding relay to disconnect the circuit connection between the main channel and the EIS module. Subsequently, the host computer needs to restore the connection status of the non-main channel. This requires the host computer to accurately memorize or obtain the initial connection status information of the non-main channel before the EIS test. This information can be recorded and stored in the memory or other storage media before the host computer controls the DEIS relay module to switch channels. When the host computer confirms that the connection status of the non-main channel needs to be restored, the initial status information is read from the storage, and a control instruction is generated based on this information and sent to the DEIS relay module. The DEIS relay module drives the corresponding relay according to the instruction to adjust the connection status of the non-main channel back to the initial state.

[0058] In the embodiment of the present application, due to the use of technical means such as controlling the charging and discharging equipment to start the main channel constant current step to stabilize the battery, judging the EIS start conditions in combination with the battery status and the duration of the constant current step, reasonably arranging the test sequence according to the EIS start status of the non-main channel, using the DEIS relay module to accurately switch channels, injecting AC disturbance current and obtaining calculated impedance data, it effectively avoids the influence of battery status instability and channel interference on the test, and solves the problems of difficulty in accurately judging the test timing and confusion in multi-channel testing, thereby achieving the goal of making the test results more accurately reflect the electrochemical characteristics of the battery and ensuring that the battery is tested in a suitable state.

[0059] After combining the above content, the following is a more detailed description of the process of the method provided by this implementation. Figure 3 , is another flow chart of the dynamic EIS testing method based on charging and discharging equipment in an embodiment of the present application.

[0060] S301, sending an instruction to the EIS module to stop injecting AC disturbance current;

[0061] The "command to stop injecting AC disturbance current" refers to the signal sent by the host computer to the EIS module to control it to stop generating and outputting AC disturbance current. This command carries specific coded information, which the EIS module can recognize and execute the corresponding operation after receiving it.

[0062] This step is performed after the EIS test step is completed. In battery testing scenarios, whether studying battery performance in the laboratory or conducting product quality inspections on a battery production line, once the EIS test completes and the required impedance data is obtained, the AC perturbation current injection must be stopped to avoid affecting the battery's subsequent status. Specifically, after the host computer confirms that the EIS test step has concluded and the relevant impedance data has been accurately acquired and recorded, it generates a data packet containing the instruction to stop injecting the AC perturbation current according to a pre-set communication protocol. This data packet is encapsulated in the format specified by the communication protocol and contains information such as the instruction code and the address of the target device (i.e., the EIS module). The host computer then transmits the data packet via a communication link connected to the EIS module, such as a serial port or SPI interface. Upon receiving the data packet, the EIS module's communication receiving circuit parses it and, upon identifying it as the instruction to stop injecting the AC perturbation current, controls the internal signal generator to stop operating, thereby ceasing the generation and output of the AC perturbation current. After sending the instruction, the host computer also starts a timer to wait for the EIS module to return a feedback signal indicating that the current has returned to zero, allowing for subsequent operations.

[0063] S302, after detecting the feedback signal that the AC disturbance current has returned to zero, waiting for a set time period so that the AC disturbance current completely stops outputting;

[0064] The "AC disturbance current zero feedback signal" refers to the signal sent by the EIS module to the host computer after receiving the instruction to stop injecting the AC disturbance current and stopping current generation, indicating that the current output has stopped (i.e., the current value has reached zero). This signal can be a simple level change signal or specifically encoded data information. The "set duration" refers to a pre-set time interval used to ensure that the AC disturbance current output in the hardware circuit completely stops, preventing residual current from affecting subsequent operations. The duration is determined based on the specific hardware characteristics and test requirements.

[0065] This step is executed immediately after the host computer receives the feedback signal that the AC disturbance current has returned to zero. In the entire battery test process, when the EIS test is completed and the AC disturbance current injection is stopped, it is necessary to ensure that the current has completely stopped before subsequent operations such as channel recovery can be performed to ensure the safety of the battery and test equipment and avoid accidents caused by residual current. Specifically, after the host computer issues an instruction to stop injecting the AC disturbance current, it will continuously monitor the feedback signal line connected to the EIS module. When the feedback signal representing that the AC disturbance current has returned to zero is detected, the host computer starts the internal timer and starts counting the waiting time for the set duration. During the waiting process, the host computer will not perform other operations that may interfere with the complete cessation of the current. For example, during this period, the host computer will not send new control instructions to the EIS module or DEIS relay module, nor will it perform other data acquisition operations to avoid affecting the stability of the hardware circuit. After waiting for the set duration, the host computer believes that the AC disturbance current has completely stopped output, and it is now safe to proceed to the next channel switching or other operations. If an abnormal situation occurs during the waiting process, such as the feedback signal suddenly disappears or an incorrect signal state occurs, the host computer will recheck the communication connection and the status of the EIS module, and resend the stop command and wait again if necessary.

[0066] S303, controlling the relay in the DEIS relay module to disconnect from the main channel;

[0067] "Relay" is a key component in the DEIS relay module. It is an electrical control device with a control system (input circuit) and a controlled system (output circuit). It is usually used in automated control circuits. It is actually an automatic switch that uses a small current to control a large current operation. In this step, it is used to cut off the connection between the main channel and the EIS module.

[0068] This step is performed after the AC disturbance current has completely ceased output. During the battery test, after the EIS test is completed and the AC disturbance current has ceased, the EIS module needs to be disconnected from the main channel to avoid affecting the subsequent charging and discharging operations of the battery and to ensure the normal operation of the test equipment. Specifically, after the host computer confirms that the AC disturbance current has completely ceased output, that is, after completing the waiting time set in step S302, it will generate a command data packet to control the relay operation in the DEIS relay module according to the pre-set control logic. This data packet contains information such as the identification of the relay to be controlled and the disconnection operation command. The host computer then sends the command data packet via a communication line connected to the DEIS relay module in the charging and discharging equipment, such as a serial port or internal bus. After receiving the data packet, the communication receiving circuit of the DEIS relay module parses it and identifies the command to control the relay to disconnect the main channel. Next, the control circuit of the DEIS relay module drives the corresponding relay to operate, causing the normally open contacts of the relay to open, thereby severing the connection between the main channel and the EIS module. During relay operation, the host computer can confirm whether the main channel has been successfully disconnected by monitoring the relay's feedback signal or detecting the status of related circuits. If the disconnection operation fails, such as a relay failure that prevents normal disconnection, the host computer will record the error information and attempt to resend the disconnection command, or issue an alarm to notify the operator for inspection and resolution.

[0069] S304, detecting the voltage value at both ends of each non-main channel through the DEIS relay module, and calculating the channel difference between the voltage value and the main channel voltage;

[0070] The "voltage value" refers to the potential difference between the two ends of a non-primary channel. Its magnitude reflects the current electrical status of the channel and is typically measured in volts (V). The "primary channel voltage" is the current voltage of the primary channel and serves as a benchmark for comparison with the non-primary channel voltage. The "channel difference" represents the difference between the non-primary channel voltage and the primary channel voltage. This difference can be used to determine whether the non-primary channel is functioning properly, providing a basis for determining whether to perform subsequent connection recovery operations.

[0071] This step is performed after controlling the DEIS relay module to disconnect the main channel from the EIS module. After the battery test completes the EIS test phase and the channels are restored to their original state, it is necessary to determine whether the status of each non-main channel is normal to ensure the safety and stability of the restoration operation. Specifically, after the host computer confirms that the DEIS relay module has successfully disconnected the main channel from the EIS module, it sends a detection instruction to the DEIS relay module. This instruction contains an operation command for the DEIS relay module to detect the voltage across each non-main channel. After receiving the instruction, the DEIS relay module's internal voltage detection circuit begins operating, measuring the voltage across each non-main channel in turn. After the measurement is completed, the voltage value of each non-main channel is fed back to the host computer via the communication line. After receiving these voltage values, the host computer obtains the current voltage value of the main channel (which can be previously recorded or obtained in real time). The host computer then calculates the difference between the voltage value of each non-main channel and the voltage value of the main channel, i.e., channel difference = non-main channel voltage value - main channel voltage value. During the calculation process, the host computer will mark and store the data for subsequent analysis and processing. If a non-primary channel fails to obtain a voltage value, the host computer will record the relevant error information and treat it specially in subsequent processing.

[0072] S305: If the channel difference exceeds the set channel voltage difference threshold, the corresponding channel is skipped and the abnormality is recorded without performing the connection recovery operation;

[0073] "Set channel voltage difference threshold" is a pre-set voltage difference standard used to determine whether the status of the non-main channel is normal. Different test scenarios and equipment may set different thresholds. "Skip the corresponding channel" means ignoring the channel and not performing the connection recovery action when performing the channel connection recovery operation to avoid circuit failures that may be caused by channel abnormalities. "Record abnormalities" means recording the abnormal conditions of the channel to facilitate subsequent troubleshooting and analysis. The recorded content may include channel number, abnormal time, channel difference and other information. "Connection recovery operation" means restoring the non-main channel to the initial connection state before the EIS test, so that the charging and discharging equipment can perform subsequent operations normally.

[0074] This step is performed immediately after calculating the channel difference in the previous step. When the battery test completes the EIS test and prepares to restore channel connections, the comparison of the channel difference with the set threshold determines whether to restore connections for non-master channels to ensure safe and stable operation of the entire test system. Specifically, after calculating the channel difference, the host computer compares the channel difference of each non-master channel with the set channel voltage difference threshold. For a non-master channel, if its channel difference is greater than the set threshold (e.g., greater than 0.5V) or less than the negative value of the set threshold (e.g., less than -0.5V), the host computer determines that the channel has an abnormality. In this case, the host computer skips restoring the connection for that channel and does not send a command to the DEIS relay module to restore the connection for that channel. The host computer also records the channel abnormality in the system log. The recorded information includes, but is not limited to, the channel number, the current time, the measured channel difference, and the set threshold. This allows technicians to quickly locate the abnormal channel and analyze the possible cause of the problem by reviewing the log when the test system needs to be maintained or troubleshooted. For example, if the channel difference of a certain channel is found to be abnormally large, it may be that the battery connected to the channel is faulty, or the channel line has a short circuit or open circuit.

[0075] S306: If the channel difference does not exceed the set channel voltage difference threshold, perform a connection recovery operation.

[0076] The "channel difference" represents the difference between the non-primary channel voltage and the primary channel voltage, calculated in step S304. It reflects the degree of deviation between the non-primary and primary channel voltages. The "connection recovery operation" restores the non-primary channel to its initial connection state before the EIS test, allowing the charging and discharging equipment to perform subsequent charging, discharging, or other testing operations normally, ensuring the continuity of the battery testing process and the stability of the equipment operation.

[0077] This step is performed after calculating the channel difference and comparing it with the set threshold. It is executed only if the channel difference is determined to be within the threshold. After the battery test completes the EIS test phase, restoring the channel connection status is a critical step to ensure normal device operation. Specifically, the host computer compares the channel difference of each non-master channel with the set threshold. If a non-master channel's channel difference is found to be within the set threshold range (greater than or equal to the lower threshold and less than or equal to the upper threshold), it determines that the channel is normal and connection restoration can be performed. Based on pre-set connection restoration logic, the host computer generates instructions to control the DEIS relay module. These instructions contain connection restoration information for each normal non-master channel, such as the target connection location and connection order. The host computer then transmits the instructions via a communication channel connected to the DEIS relay module, such as a serial port or internal bus. Upon receiving the instructions, the DEIS relay module's internal control circuit activates the corresponding relay according to the instructions, restoring the non-master channel to its initial connection state before the EIS test. During the connection recovery process, the host computer monitors the operating status of the DEIS relay module in real time and confirms the successful restoration of each non-master channel by detecting the relay's feedback signal or related circuit status. If an anomaly occurs during the connection recovery process, such as a relay failing to operate properly, the host computer records the error message and attempts to resend the connection recovery command. If multiple attempts are unsuccessful, an alarm is issued to notify the operator for inspection and resolution.

[0078] In the embodiment of the present application, due to the adoption of technical means of sending an instruction to the EIS module to stop injecting AC disturbance current, waiting for a set time after the detection current returns to zero, controlling the DEIS relay module to disconnect the main channel connection, detecting the non-main channel voltage and calculating the difference with the main channel voltage, and deciding whether to perform the connection recovery operation based on the comparison result of the difference and the threshold value, it is possible to effectively avoid the residual current affecting subsequent operations and prevent circuit failures caused by voltage mismatch, thereby achieving the technical effect of ensuring the safety and reliability of channel connection, reducing the risk of system failure, and ensuring that the battery system stably returns to normal working state after testing.

[0079] The following describes the test system in the embodiment of the present invention from the perspective of hardware processing. Figure 4 , is a schematic diagram of a physical device structure of a test system in an embodiment of the present application.

[0080] It should be noted that Figure 4 The structure of the test system shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0081] like Figure 4As shown, the test system includes a central processing unit (CPU) 401, which can perform various appropriate actions and processes, such as the methods described in the above embodiments, based on programs stored in a read-only memory (ROM) 402 or programs loaded from a storage unit 408 into a random access memory (RAM) 403. RAM 403 also stores various programs and data required for system operation. CPU 401, ROM 402, and RAM 403 are interconnected via a bus 404. An input / output (I / O) interface 405 is also connected to bus 404.

[0082] The following components are connected to the I / O interface 405: an input section 406 including an audio input device, push button switches, and the like; an output section 407 including a liquid crystal display (LCD), an audio output device, indicator lights, and the like; a storage section 408 including a hard disk and the like; and a communication section 409 including a network interface card such as a LAN (Local Area Network) card or a modem. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to the I / O interface 405 as needed. Removable media 411, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, is installed in the drive 410 as needed, so that computer programs read from the removable media can be installed in the storage section 408 as needed.

[0083] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for executing the methods illustrated in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 409 and / or installed from removable media 411. When executed by central processing unit (CPU) 401, the computer program performs the various functions defined in the present invention.

[0084] It should be noted that specific examples of computer-readable storage media may include, but are not limited to, an electrical connection having one or more conductors, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0085] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Each box in the flowchart or block diagram can represent a module, program segment, or part of the code, and the above-mentioned module, program segment, or part of the code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings.

[0086] Specifically, the test system of this embodiment includes a processor and a memory. The memory stores a computer program. When the computer program is executed by the processor, the dynamic EIS test method based on the charge-discharge device provided in the above embodiment is implemented.

[0087] As another aspect, the present invention further provides a computer-readable storage medium, which may be included in the test system described in the above embodiments, or may exist independently and not incorporated into the test system. The storage medium carries one or more computer programs, which, when executed by a processor of the test system, enable the test system to implement the dynamic EIS test method based on a charge-discharge device provided in the above embodiments.

[0088] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0089] As used in the above embodiments, the term “when” may be interpreted to mean “if” or “after” or “in response to determining that” or “in response to detecting that”, depending on the context. Similarly, the phrases “upon determining that” or “if (stated condition or event) is detected” may be interpreted to mean “if determining that” or “in response to determining that” or “upon detecting (stated condition or event)” or “in response to detecting (stated condition or event)”, depending on the context.

[0090] Those skilled in the art will appreciate that all or part of the process steps in the above-described method embodiments can be implemented by a computer program instructing the relevant hardware. The program can be stored in a computer-readable storage medium, and when executed, the program can include the process steps in the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM or random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A dynamic EIS test method based on a charge-discharge device, applied to a host computer in a test system, characterized in that: The method comprises: Control the charging and discharging equipment to start the constant current step of the main channel to keep the battery in a stable charging and discharging state. The main channel refers to the circuit channel in the charging and discharging equipment mainly used to connect the battery for charging and discharging. It is the channel that undertakes the main charging and discharging tasks in a multi-channel charging and discharging equipment; After determining that the battery meets the EIS start condition, determining the EIS start state of the non-main channel; After determining that the EIS startup state is the inactive state, switching the channel through the DEIS relay module, the DEIS relay module is built into the charging and discharging device; After confirming that the channel switching is completed, controlling the EIS module to continuously inject an AC disturbance current of a preset amplitude into the battery; Acquire a response voltage signal and calculate impedance data in real time, wherein the impedance data includes at least impedance amplitude and impedance phase; The steps for switching channels through the DEIS relay module include: The relay in the DEIS relay module cuts off the connection of the non-main channel and connects the EIS module in parallel to the main channel.

2. The method according to claim 1, characterized in that After the step of controlling the charging and discharging equipment to start the constant current step, it also includes: Real-time monitoring of battery status to obtain battery status information, wherein the battery status information includes at least battery voltage information and battery state of charge information; Get the duration of the constant current step; If the battery status information and the duration are greater than a set EIS start-up standard value, it is determined that the battery meets the EIS start-up condition.

3. The method according to claim 1, characterized in that After the step of determining the EIS start state of the non-master channel, the method further includes: If the EIS startup state is the startup state, a queue waiting instruction is sent to the DEIS relay module; If the EIS startup state is the inactive state, an EIS startup instruction is sent to the DEIS relay module.

4. The method according to claim 1, wherein After the steps of obtaining the response voltage signal and calculating the impedance data in real time, the method further includes: After confirming that the EIS work step is completed, the DEIS relay module is controlled to cut off the connection with the main channel and restore the connection of the non-main channel according to the initial channel connection state. The initial channel connection state is the connection state of the non-main channel before the channel is switched by the DEIS relay module.

5. The method according to claim 4, characterized in that After confirming that the EIS step is completed, controlling the DEIS relay module to cut off the connection with the main channel and restore the connection of the non-main channel according to the initial channel connection state, specifically includes: Sending an instruction to the EIS module to stop injecting the AC disturbance current; After detecting a feedback signal indicating that the AC disturbance current has returned to zero, waiting for a set time period so that the AC disturbance current completely stops being output; Controlling the relay in the DEIS relay module to disconnect from the main channel; Detecting the voltage value at both ends of each non-main channel through the DEIS relay module, and calculating the channel difference between the voltage value and the main channel voltage; If the channel difference exceeds the set channel voltage difference threshold, the corresponding channel is skipped and the abnormality is recorded without performing the connection recovery operation; If the channel difference does not exceed the set channel voltage difference threshold, a connection recovery operation is performed.

6. The method according to claim 1, characterized in that After determining that the EIS startup state is the inactive state, after the step of switching the channel through the DEIS relay module, the method further includes: The connectivity status of each channel is displayed by a plurality of LED lights, wherein the LED lights are arranged in each channel; Obtaining the startup status of the plurality of LED lights; If it is detected that the startup state is startup, a channel switching failure reminder is sent to the display terminal.

7. A testing system, characterized in that: The test system includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to cause the test system to execute the method according to any one of claims 1 to 6.

8. A computer-readable storage medium comprising instructions, characterized in that: When the instruction is executed on a test system, the test system is caused to execute the method according to any one of claims 1 to 6.

9. A computer program product, characterized in that When the computer program product is run on a test system, the test system is caused to perform the method according to any one of claims 1 to 6.

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