Dielectric layer moisture content-leakage current collaborative analysis method and system

Abstract

The invention provides a dielectric layer moisture content-leakage current collaborative analysis method and system, and relates to the technical field of electronic components, the method is applied to a test system, the test system comprises a capacitor and an electrochemical workstation, and the method comprises the following steps: placing the capacitor to be tested in a preset temperature and humidity for a preset time period, and taking out the capacitor to be tested; connecting the capacitor with an electrochemical workstation; the working mode of the electrochemical workstation is switched to a cyclic volt-ampere test mode, then the capacitor is scanned through the periodic triangular wave potential according to preset test parameters, current response data of the capacitor under different potentials are obtained, a cyclic volt-ampere curve is generated according to the current response data, and excess current of a dielectric layer of the capacitor is extracted. Integrating the curve of the excess current changing along with time to obtain the total electric quantity; the moisture content of the dielectric layer is obtained by combining the Faraday law and the electrolyzed water reaction law; and the leakage current characteristic of the capacitor is further obtained. According to the invention, rapid and quantitative evaluation of the capacitor is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic components, in particular to a dielectric layer moisture content-leakage current collaborative analysis method and system. BACKGROUND

[0002] In electronic systems, laminated aluminum solid electrolytic capacitors have become core components in key fields such as consumer electronics, communication equipment, industrial control and automotive electronics. However, due to its characteristics of being easily affected by moisture, during its life cycle, moisture often penetrates into the dielectric layer (aluminum oxide layer) inside the capacitor, thereby causing chemical degradation of the dielectric, and also forming a conductive path through interface reaction, thereby increasing the leakage current and severely shortening its life. Therefore, it is necessary to monitor the influence of moisture on laminated aluminum solid electrolytic capacitors in real time.

[0003] In related technologies, evaluating the moisture sensitivity and leakage current reliability of capacitors often relies on high-temperature and high-humidity load tests or long-term stability tests. Although these tests can reflect the final performance changes, they often need to be performed for hundreds or even thousands of hours, which cannot meet the rapid screening and real-time monitoring needs of the research and development process. Moreover, traditional detection methods are post-evaluation, which cannot truly evaluate capacitors in use, thereby affecting the evaluation effect of capacitors. SUMMARY

[0004] The problem solved by the present application is how to improve the real-time and convenience of capacitor moisture evaluation.

[0005] To solve the above problems, the present application provides a dielectric layer moisture content-leakage current collaborative analysis method and test system.

[0006] In a first aspect, the present application provides a dielectric layer moisture content-leakage current collaborative analysis method, which is applied to a test system including a capacitor and an electrochemical workstation, and the method comprises: placing the capacitor to be tested in a preset temperature and a preset humidity for a preset duration, and then connecting the capacitor to the electrochemical workstation; switching the working mode of the electrochemical workstation to a cyclic voltammetry test mode, and then scanning the capacitor by a periodic triangular wave potential according to preset test parameters to obtain current response data of the capacitor at different potentials, and generating a cyclic voltammetry curve according to the current response data; extracting the excess current of the dielectric layer of the capacitor from the cyclic voltammetry curve, and integrating the excess current-time curve to obtain a total electric quantity; According to the total electric quantity, the moisture content of the dielectric layer is obtained by combining Faraday's law and the electrolytic water reaction rule. According to the shape characteristics of the cyclic voltammogram and the water content, the leakage current characteristics of the capacitor are obtained.

[0007] Optionally, the scanning of the capacitor by the periodic triangular wave potential obtains current response data of the capacitor at different potentials, including: Starting the electrochemical workstation, and automatically applying triangular wave potential scanning to the capacitor according to a preset voltage scanning range, a preset scanning rate and a preset cycle number; Wherein, the periodic triangular wave potential scanning is positively scanned from 0V to 10V, and then reversely scanned to 0V to form a cycle, and in each cycle, the current response data of the capacitor at different potentials is obtained by the electrochemical workstation; Wherein, the current response includes charging current and discharging current of the capacitor in the process of positive scanning and reverse scanning; Repeating the triangular wave potential scanning until the preset cycle number is completed, and obtaining the current response data of the capacitor at different potentials.

[0008] Optionally, the preset test parameters include: preset voltage scanning range, preset scanning rate and preset cycle number of the electrochemical workstation; The preset voltage scanning range of the electrochemical workstation is 0-10V, the starting voltage is 0V, and the terminal voltage is 10V; the preset scanning rate of the electrochemical workstation is 0.5V / s; the preset cycle number of the electrochemical workstation is 5 cycles.

[0009] Optionally, the generation of the cyclic voltammogram according to the current response data includes: Arranging the current response data in order of potential to form a current-potential data point set; Taking potential as abscissa and current as ordinate, the current-potential data point set is drawn in a two-dimensional coordinate system to generate the cyclic voltammogram.

[0010] Optionally, the extraction of the excess current of the dielectric layer of the capacitor from the cyclic voltammogram, and the integration of the change of the excess current with time to obtain the total electric quantity, includes: According to the cyclic voltammogram, the reference current of the dielectric layer of the capacitor is determined; According to the difference between each current value in the current response data and the reference current, the excess current is obtained; The curve of the change of the excess current with time is divided into multiple time intervals; determining a time interval according to the time interval, and generating a product of the excess current and the time interval in each of the time intervals respectively; adding the products of the excess current and the time interval in all of the time intervals to obtain the total electric quantity.

[0011] Optionally, the set Faraday's law and the water electrolysis reaction rule are used to obtain the water content of the dielectric layer according to the total electric quantity, including: obtaining an electrochemical equivalent of the water electrolysis reaction, the electrochemical equivalent being a ratio of a molar mass of a substance to a Faraday constant and a valence of the substance; generating a mass of the water electrolysis in the dielectric layer according to the total electric quantity and the electrochemical equivalent; obtaining the water content of the dielectric layer according to the mass of the water electrolysis in the dielectric layer.

[0012] Optionally, the leakage current characteristic of the capacitor is obtained according to the morphological feature of the cyclic voltammogram and the water content, including: determining whether the capacitor has an abnormal leakage current characteristic according to the morphological feature of the cyclic voltammogram, wherein the morphological feature includes an abnormal current peak, and the abnormal current peak includes an asymmetric peak and a redox current peak; if the cyclic voltammogram has the asymmetric peak or the redox current peak, it is determined that the capacitor has an abnormal leakage current characteristic; if the cyclic voltammogram is approximately rectangular and does not have the asymmetric peak and the redox current peak, the water content is compared with a preset water content threshold value; if the water content exceeds the preset water content threshold value, it is determined that the capacitor has an abnormal leakage current characteristic; if the water content is within the preset water content threshold value, it is determined that the capacitor has a normal leakage current characteristic.

[0013] Optionally, the capacitor is connected to the electrochemical workstation, including: connecting an anode pin of the capacitor to a working electrode interface of the electrochemical workstation, and connecting a cathode pin of the capacitor to a counter electrode interface of the electrochemical workstation.

[0014] In a second aspect, a dielectric layer water content-leakage current collaborative analysis system is provided, including a memory and a processor; the memory is configured to store a computer program; the processor is configured to implement the dielectric layer water content-leakage current collaborative analysis method when the computer program is executed.

[0015] In a third aspect, the present application provides a computer readable storage medium, wherein a computer program is stored on the storage medium, and when the computer program is executed by a processor, a dielectric layer moisture content-leakage current collaborative analysis method is implemented.

[0016] The dielectric layer moisture content-leakage current collaborative analysis method and system of the present application ensures that the capacitor reaches a stable state before testing by setting a pretreatment step, i.e., placing the capacitor to be tested in a preset temperature and humidity for a preset duration, and then connecting it with an electrochemical workstation, eliminating the short-term interference of environmental factors on the moisture distribution of the dielectric layer, providing a basis for subsequent accurate measurement, and ensuring the accuracy and repeatability of the test results.

[0017] The current response of the capacitor at different potentials is accurately captured through cyclic voltammetry testing, and the moisture in the dielectric layer can be excited to undergo electrolysis through periodic triangular wave potential scanning, thereby reflecting excess current in the current response data. This excess current is directly related to the moisture content in the dielectric layer, providing key data for subsequent quantitative analysis. The total electric quantity obtained by integrating the excess current, combined with Faraday's law, is used to calculate the moisture content in the dielectric layer. This method not only realizes quantitative analysis of moisture content, but also provides a fast and non-destructive detection method. Compared with traditional high-temperature and high-humidity load tests or long-term stability tests, this method can provide accurate moisture content data in a short time, greatly improving the detection efficiency. By analyzing the morphological characteristics of the cyclic voltammetry curve (such as whether an asymmetric peak or additional redox current peak appears), the electrochemical behavior of the capacitor can be directly reflected. Combined with the quantitative analysis of moisture content, the leakage current characteristics of the capacitor can be more comprehensively evaluated. Not only can potential problems of the capacitor be quickly identified, but also data support can be provided for the optimization of production processes, ensuring the reliability and stability of the capacitor in actual application.

[0018] In summary, the present application realizes fast and quantitative evaluation of laminated aluminum solid-state electrolytic capacitors. The pretreatment step ensures the stability of the test environment, the cyclic voltammetry test provides accurate current response data, the excess current integration realizes quantitative analysis of moisture content, and the morphological characteristics of the cyclic voltammetry curve further verify the leakage current characteristics of the capacitor. Not only does it improve detection efficiency and accuracy, but it also provides strong support for the optimization of capacitor production processes and quality control. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The flowchart of the dielectric layer moisture content-leakage current collaborative analysis method of the embodiment of the present application; Figure 2 The capacitor cyclic voltammetry curve is approximately rectangular, and the schematic diagram of the embodiment of the present application; Figure 3 The cyclic voltammogram and water electrolysis process schematic diagram of the long-term placed capacitor of the embodiment of the present application; Figure 4 The I-T curve and excess current integral schematic diagram in the water electrolysis process of the embodiment of the present application; Figure 5 The structural schematic diagram of the electronic device of the embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to make the above objectives, characteristics and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the drawings. Although some embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms, and should not be interpreted as being limited to the embodiments described herein, on the contrary, these embodiments are provided to make the present application more thorough and complete. It should be understood that the drawings and embodiments of the present application are only for illustrative purposes, and are not intended to limit the scope of protection of the present application.

[0021] It should be understood that each step described in the method embodiments of the present application can be performed in different order and / or in parallel. In addition, the method embodiments can include additional steps and / or omit the steps shown. The scope of the present application is not limited in this respect.

[0022] The term "comprising" and its variants as used herein are open-ended, that is "including but not limited to"; the term "based on" is "at least partially based on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". Related definitions of other terms will be given in the following description. It should be noted that the "first", "second", etc. concepts mentioned in the present application are only used to distinguish different devices, modules or units, and are not intended to limit the order or interdependence of the functions performed by these devices, modules or units.

[0023] It should be noted that the modification of "one" or "multiple" mentioned in the present application is illustrative and not limiting, and those skilled in the art should understand that unless otherwise explicitly indicated in the context, it should be understood as "one or more".

[0024] The names of the messages or information exchanged between the multiple devices in the embodiments of the present application are only for illustrative purposes, and are not intended to limit the scope of these messages or information.

[0025] It should be noted that the information (including but not limited to user equipment information, user personal information, etc.), data (including but not limited to data for analysis, stored data, displayed data, etc.) and signals involved in the present application are authorized by the user or fully authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards of relevant countries and regions, and provide corresponding operation portal for user to choose authorization or rejection.

[0026] As shown in Figure 1 The dielectric layer moisture content-leakage current collaborative analysis method provided by the embodiment of the present application is applied to a test system, and the test system comprises a capacitor and an electrochemical workstation.

[0027] Specifically, the present embodiment takes an electrochemical workstation (for example, Shanghai Chenhua CHI660E) with high-precision current detection and fast potential control capability as the core test equipment. The workstation integrates multiple measurement modes such as cyclic voltammetry (CV) and chronocoulometry (I-T), and its wide potential range (≥±10V) and high current resolution (usually ≤pA level) can accurately capture the weak current response of the laminated aluminum solid capacitor under high-voltage scanning. In view of the dielectric layer moisture content and leakage current characteristics collaborative analysis requirements of the laminated aluminum solid capacitor, a standardized cyclic voltammetry (C-V) test and subsequent current-time (I-T) characteristic observation process is designed.

[0028] The dielectric layer moisture content-leakage current collaborative analysis method comprises: After the capacitor to be tested is placed in a preset temperature and a preset humidity for a preset duration, the capacitor is connected with the electrochemical workstation.

[0029] Specifically, before the dielectric layer moisture content and leakage current characteristics test of the capacitor is performed, the capacitor needs to be pretreated. The specific steps are as follows: the capacitor is placed in a constant temperature and humidity environment (for example, temperature 25±2℃, humidity 60±5%RH) for 30 minutes. To ensure that the dielectric layer moisture distribution inside the capacitor reaches a relatively stable state, thereby eliminating the short-term interference of environmental factors on the test results, and ensuring the accuracy and repeatability of the test.

[0030] After the pretreatment is completed, the capacitor is connected with the electrochemical workstation, and the subsequent test is prepared. The anode pin of the capacitor is connected to the working electrode (WE) interface of the electrochemical workstation through a wire, the cathode pin is connected to the counter electrode (CE) interface, and a multimeter is used to confirm that there is no leakage contact between the electrodes, and the electrical isolation of the test system is ensured.

[0031] Switch the working mode of the electrochemical workstation to a cyclic voltammetry test mode, and then scan the capacitor by a periodic triangular wave potential according to preset test parameters, to obtain current response data of the capacitor under different potentials, and generate a cyclic voltammogram according to the current response data.

[0032] Specifically, the working mode of the electrochemical workstation is switched to a cyclic voltammetry test mode. Cyclic voltammetry is a commonly used electrochemical analysis method, which can record the current response of an electrode under different potentials by applying a periodic potential scan.

[0033] The preset test parameters include: the voltage scan range is set to 0-10V. The starting voltage is 0V, and the ending voltage is 10V. The potential range is higher than the theoretical decomposition potential of water (about 1.23V), which can fully stimulate and observe the Faraday current peak of water electrolysis, and at the same time covers the typical working voltage range of the capacitor, which is beneficial to evaluate its behavior under high field strength. The scan rate is set to 0.5V / s, which balances the signal resolution and test efficiency. Too fast scan rate (such as >1V / s) will cause the reaction kinetics on the electrode surface to lag, and the excess current peak of water electrolysis will be broadened or submerged in the background current; too slow scan rate (such as <0.2V / s) will prolong the test time and increase the influence of environmental interference (such as humidity fluctuation) on the results. The number of cycles is set to 5 cycles (a total of 10 scans). The first cycle is mainly used to activate the adsorbed water and defect sites on the surface of the dielectric layer, and the water electrolysis reaction tends to be stable in the subsequent cycles, so the C-V curves of the 2nd-5th cycles are taken for water content calculation to exclude the irreversible activation effect of the first cycle.

[0034] After starting the test, the electrochemical workstation automatically applies a periodic triangular wave potential scan (from 0V to 10V in the positive direction, and then to 0V in the reverse direction), and synchronously records the current response under different potentials to generate a cyclic voltammogram. During the test, it is monitored in real time whether the current signal abnormally fluctuates (such as suddenly jumps or drifts), and if an abnormality is found, the test is paused and the electrode connection or environmental interference problem is checked.

[0035] Extract the excess current of the dielectric layer of the capacitor from the cyclic voltammogram, and integrate the excess current-time curve to obtain the total electric quantity.

[0036] Specifically, the excess current is extracted from the cyclic voltammogram, where the excess current refers to the additional current generated by the electrolysis reaction of moisture in the dielectric layer during capacitor charging. Specifically, the current difference between the forward scan (anodic electrolysis) and the reverse scan (cathodic electrolysis) is calculated, the aluminum matrix background current (calibrated by testing a blank aluminum sheet) is subtracted, and the excess current caused only by the electrolysis of moisture is obtained. The curve of the excess current with respect to time is integrated to obtain the total electric quantity, which is closely related to the moisture content in the dielectric layer and provides key data for subsequent quantitative analysis of moisture content.

[0037] According to the total electric quantity, the moisture content of the dielectric layer is obtained by combining Faraday's law and the electrolysis water reaction rule.

[0038] Specifically, Faraday's law is used to describe the relationship between the electric quantity passing through the electrode and the mass of the substance undergoing electrode reaction. In the present application, Faraday's law and the electrolysis water reaction rule are used to calculate the moisture content in the dielectric layer according to the total electric quantity obtained by integration. The specific calculation process includes: determining the electrolytic equivalent of the water reaction, and then calculating the mass of the moisture according to the total electric quantity and the electrolytic equivalent; the obtained quantitative information of the moisture in the dielectric layer provides an important basis for evaluating the reliability of the capacitor.

[0039] According to the morphological characteristics of the cyclic voltammogram and the moisture content, the leakage current characteristics of the capacitor are obtained.

[0040] Specifically, the morphological characteristics of the cyclic voltammogram (such as the presence or absence of asymmetric peaks or additional redox current peaks) directly reflect the electrochemical behavior of the capacitor. Combined with the previously obtained moisture content information, the leakage current characteristics of the capacitor can be more comprehensively evaluated. For example, if the cyclic voltammogram shows asymmetric peaks or additional current peaks, it may indicate that there are electrochemical side reactions inside the capacitor, resulting in increased leakage current. By analyzing these morphological characteristics and moisture content, it can be determined whether the leakage current characteristics of the capacitor are normal, thereby providing strong support for the quality evaluation and reliability prediction of the capacitor.

[0041] The dielectric layer moisture content-leakage current collaborative analysis method of the present embodiment ensures that the capacitor reaches a stable state before testing by setting a pretreatment step, i.e. placing the capacitor to be tested in a preset temperature and humidity for a preset duration, and then connecting it to an electrochemical workstation. This eliminates short-term environmental factors that interfere with the distribution of moisture in the dielectric layer, providing a basis for subsequent accurate measurement and ensuring the accuracy and repeatability of the test results.

[0042] The current response of the capacitor at different potentials is accurately captured by cyclic voltammetry test, and the water in the dielectric layer can be electrolyzed by periodic triangular wave potential scanning, so that the excess current is reflected in the current response data, and the excess current is directly related to the water content in the dielectric layer, which provides key data for subsequent quantitative analysis. The total electric quantity obtained by integrating the excess current is combined with Faraday's law to calculate the water content in the dielectric layer. This method not only realizes the quantitative analysis of water content, but also provides a fast and non-destructive detection method. Compared with the traditional high temperature and high humidity load test or long term stability test, this method can provide accurate water content data in a short time, greatly improving the detection efficiency. By analyzing the morphological characteristics (such as whether an asymmetric peak or an additional redox current peak appears) of the cyclic voltammetry curve, the electrochemical behavior of the capacitor can be directly reflected. Combined with the quantitative analysis of water content, the leakage current characteristics of the capacitor can be more comprehensively evaluated. Not only can the potential problems of the capacitor be quickly identified, but also data support can be provided for the optimization of production process, ensuring the reliability and stability of the capacitor in actual application.

[0043] In summary, the embodiment realizes the rapid and quantitative evaluation of the laminated aluminum solid-state electrolytic capacitor. The pretreatment step ensures the stability of the test environment, the cyclic voltammetry test provides accurate current response data, the excess current integration realizes the quantitative analysis of water content, and the morphological characteristics of the cyclic voltammetry curve further verify the leakage current characteristics of the capacitor. Not only improves the detection efficiency and accuracy, but also provides strong support for the production process optimization and quality control of the capacitor.

[0044] Optionally, the scanning of the capacitor by the periodic triangular wave potential to obtain the current response data of the capacitor at different potentials comprises: starting the electrochemical workstation, and automatically applying triangular wave potential scanning to the capacitor according to a preset voltage scanning range, a preset scanning rate and a preset cycle number; wherein the periodic triangular wave potential scanning is scanned from 0V to 10V in the positive direction, and then scanned from 10V to 0V in the reverse direction to form a cycle, and in each cycle, the current response data of the capacitor at different potentials is obtained by the electrochemical workstation; wherein the current response includes the charging current and the discharging current of the capacitor during the positive scanning and the reverse scanning; repeating the triangular wave potential scanning until the preset cycle number is completed, and obtaining the current response data of the capacitor at different potentials.

[0045] Specifically, the electrochemical workstation is started, and the working mode of the workstation is switched to a cyclic voltammetry test mode. In this mode, the electrochemical workstation automatically applies a periodic triangular wave potential scan to the capacitor according to a preset voltage scan range, a scan rate, and a cycle number.

[0046] The preset voltage scan range in the embodiment of the application is 0-10V, the starting voltage is 0V, and the terminal voltage is 10V. This range is set according to the characteristics of the water electrolysis reaction of the dielectric layer and the actual working scenario of the aluminum capacitor, so as to ensure that the Faraday current peak of the water electrolysis can be fully excited and observed, and at the same time, the typical working voltage range of the capacitor is covered, which is beneficial to the evaluation of the behavior of the capacitor under high field strength. The preset scan rate is 0.5V / s. This value is the best choice for controlling the single scan time to be the shortest and effectively suppressing the environmental noise on the premise of ensuring the integrity of the water electrolysis current peak. The preset cycle number is 5 cycles, and there are 10 scans in total. The first cycle is used to activate the adsorbed water and defect sites on the surface of the dielectric layer, and the water electrolysis reaction tends to be stable in the subsequent cycles. Therefore, the C-V curves of the 2nd to 5th cycles are taken for water content calculation, and the irreversible activation effect of the first cycle is excluded.

[0047] The periodic triangular wave potential scan is scanned from 0V to 10V in the positive direction, and then scanned from 10V to 0V in the reverse direction, forming a complete cycle. In each cycle, the electrochemical workstation records the current response data of the capacitor at different potentials through its high-precision current detection function. The current response includes the charging current and the discharging current of the capacitor during the positive scan and the reverse scan. The changes of the charging current and the discharging current can reflect the electrochemical behavior of the capacitor at different potentials, especially when the dielectric layer contains water, an additional current response, i.e., an excess current, will be generated at a specific potential, which is crucial for evaluating the leakage current characteristics of the capacitor. The triangular wave potential scan is repeated until the preset cycle number is completed, and the current response data of the capacitor at different potentials is obtained. Through multiple cycle scans, the stability and repeatability of the data can be ensured, providing a reliable basis for subsequent analysis. During the test, the abnormal fluctuations of the current signal, such as sudden jumps or drifts, are monitored in real time. If abnormalities are found, the test is paused and the electrode connection or environmental interference problem is checked. After all the cycles are completed, the C-V curve original data is exported through the matching software and saved in Excel or TXT format for future use.

[0048] In this optional embodiment, by placing the capacitor in a pre-set temperature and humidity environment for pretreatment, the short-term interference of environmental factors on the test results can be eliminated, ensuring the accuracy and repeatability of the test. Using the cyclic voltammetry test mode of the electrochemical workstation, triangular wave potential scanning is performed according to the pre-set voltage scanning range, scanning rate and cycle number, which can accurately capture the current response of the capacitor at different potentials, especially the excess current generated by water electrolysis. By integrating the curve of the excess current change with time, the total electric quantity is obtained, and combined with Faraday's law and the water electrolysis reaction rule, the water content in the dielectric layer is calculated, realizing the quantitative analysis of the water content. At the same time, by analyzing the morphological characteristics of the cyclic voltammetry curve, it can be quickly judged whether there is an abnormal current peak in the capacitor, so as to evaluate its leakage current characteristics. This process not only improves the detection efficiency, but also provides accurate water content and leakage current characteristic data in a short time, meeting the needs of rapid and efficient detection in the research and production process.

[0049] Optionally, the pre-set test parameters include: a pre-set voltage scanning range, a pre-set scanning rate and a pre-set cycle number of the electrochemical workstation. The pre-set voltage scanning range of the electrochemical workstation is 0-10V, the starting voltage is 0V, and the terminal voltage is 10V; the pre-set scanning rate of the electrochemical workstation is 0.5V / s; the pre-set cycle number of the electrochemical workstation is 5 cycles.

[0050] Specifically, the pre-set test parameters include the pre-set voltage scanning range, the pre-set scanning rate and the pre-set cycle number of the electrochemical workstation. The pre-set voltage scanning range of the electrochemical workstation is 0-10V, the starting voltage is 0V, and the terminal voltage is 10V. The setting of this range in this embodiment is based on the characteristics of the water electrolysis reaction of the dielectric layer and the actual working scenario of the aluminum capacitor. The high potential of 10V is higher than the theoretical decomposition potential of water, which can ensure that the Faraday current peak of water electrolysis is fully excited and observed, and at the same time, it covers the typical working voltage range of the capacitor, which is beneficial to evaluate its behavior under high field strength.

[0051] The pre-set scanning rate is 0.5V / s, which is selected by considering the signal resolution and test efficiency. Too fast scanning rate will cause the reaction kinetics on the electrode surface to lag, so that the excess current peak of water electrolysis is widened or submerged in the background current; while too slow scanning rate will prolong the test time and increase the influence of environmental interference on the results.

[0052] The preset number of cycles is 5 cycles, and 10 scans are performed. In this embodiment, the stability of the test and the reliability of the data are considered. The first cycle is mainly used to activate the adsorbed water and defect sites on the surface of the dielectric layer. In the subsequent cycles, the water electrolysis reaction tends to be stable, so the C-V curves of the 2nd to 5th cycles are taken to calculate the moisture content, so as to exclude the irreversible activation effect of the first cycle and ensure the accuracy and repeatability of the test results.

[0053] In this optional embodiment, by reasonably setting the above-mentioned preset test parameters, the moisture content and leakage current characteristics of the capacitor dielectric layer can be accurately detected, meeting the needs of rapid, efficient and non-destructive detection, and providing strong support for the optimization of capacitor production process and quality control.

[0054] Optionally, the generating a cyclic voltammogram according to the current response data comprises: arranging the current response data in order of potential to form a current-potential data point set; drawing the current-potential data point set in a two-dimensional coordinate system with potential as the horizontal coordinate and current as the vertical coordinate to generate the cyclic voltammogram.

[0055] Specifically, the current response data is arranged in order of potential to form a current-potential data point set. During the test, the electrochemical workstation records the current response data of the capacitor at different potentials, which is stored in the form of potential and corresponding current value. At the same time, the recorded current response data is arranged in order of potential from small to large to form a current-potential data point set. Each data point contains a potential value and a corresponding current value. The arranged data point set can clearly reflect the trend of current change with potential, providing an ordered data basis for subsequent curve drawing.

[0056] After the data is arranged, the electrochemical workstation is used to input the arranged current-potential data point set into the software. In the software, a two-dimensional coordinate system is set, in which the horizontal coordinate represents the potential with the unit of volt (V), and the vertical coordinate represents the current with the unit of ampere (A) or other appropriate current units. Each data point is marked in the coordinate system according to its potential and current value, and then these discrete data points are connected by interpolation algorithm or other curve fitting method to form a smooth curve, which is the cyclic voltammogram. This curve directly shows the current response characteristics of the capacitor at different potentials, especially the excess current peak caused by the presence of moisture in the dielectric layer, which provides a key visual basis for subsequent analysis of moisture content and leakage current characteristics. In this embodiment, the cyclic voltammogram generated by the above method not only has accurate data, but also clearly presents the characteristics of electrochemical reaction, which is helpful for quickly identifying the performance state of the capacitor.

[0057] In this optional embodiment, the method of generating cyclic voltammograms from current response data enables intuitive visualization and precise analysis of capacitor performance. By arranging the current response data in order of potential to form a set of current-potential data points, the systematicity and orderliness of the data are ensured, laying the foundation for generating accurate voltammograms. Further, plotting the curve with potential as the horizontal coordinate and current as the vertical coordinate in a two-dimensional coordinate system not only clearly shows the relationship between current and potential, but also highlights the excess current phenomenon caused by the presence of moisture in the dielectric layer. This visualization greatly facilitates quantitative analysis of the moisture content of the capacitor dielectric layer and evaluation of the leakage current characteristics.

[0058] Through the accurate drawing of cyclic voltammograms, the performance status of the capacitor can be quickly identified, including whether there is an abnormal moisture content or leakage current problem, thereby achieving efficient control and rapid screening of capacitor quality. This embodiment combines accurate data processing and intuitive graphical display, significantly improving detection efficiency and accuracy, and providing strong technical support for the reliability and quality control of capacitors.

[0059] Optionally, the excess current of the dielectric layer of the capacitor is extracted from the cyclic voltammogram, and the total electric quantity is obtained by integrating the change of the excess current with time, including: determining the reference current of the dielectric layer of the capacitor according to the cyclic voltammogram; obtaining the excess current according to the difference between each current value in the current response data and the reference current; dividing the curve of the change of the excess current with time into multiple time intervals; determining a time interval according to the time interval, and generating the product of the excess current and the time interval in each time interval, respectively; adding up the products of the excess current and the time interval in all the time intervals to obtain the total electric quantity.

[0060] Specifically, first, the reference current of the dielectric layer of the capacitor is determined by analyzing the region in the cyclic voltammogram where the water electrolysis characteristic does not appear, which represents the normal current level of the capacitor without the influence of moisture; then, the excess current is obtained according to the difference between each current value in the current response data and the reference current; that is, the current generated by the electrolysis reaction of water molecules in the dielectric layer at a specific potential during the charging process of the capacitor, which directly reflects the moisture content in the dielectric layer.

[0061] The curve of the excess current changing over time is divided into multiple time intervals to facilitate accurate integral calculation of the excess current. By segmenting the curve, the change of the excess current in each time interval can be more accurately calculated. Then, by multiplying the excess current value of each time interval with the time length of the interval, the total electric quantity generated by water electrolysis in each interval is obtained. Finally, by adding the electric quantities in each time interval, the total electric quantity generated by water electrolysis in the entire test process is obtained, and then the water content in the dielectric layer is calculated according to the Faraday law and the water electrolysis reaction rule. This process realizes quantitative analysis of the water content from the current response data, and provides key data support for evaluating the leakage current characteristics of the capacitor and the reliability of the dielectric layer.

[0062] In this optional embodiment, the water content in the dielectric layer is accurately quantitatively analyzed by accurately extracting the excess current of the dielectric layer and calculating the total electric quantity by integral calculation. First, the reference current provides a reference standard for subsequent excess current calculation, making the excess current calculation more scientific and reasonable, and accurately reflecting the electrolysis reaction degree of water in the dielectric layer. Moreover, the excess current curve is divided into multiple time intervals for integral calculation, effectively improving the accuracy of the integral, fully considering the change characteristics of the excess current over time, avoiding errors caused by overall integral, and ensuring the reliability of the total electric quantity calculation result.

[0063] This embodiment realizes quantitative analysis of the water content from the current response data, provides key data support for evaluating the water content and leakage current characteristics of the capacitor dielectric layer, improves the accuracy and reliability of the detection, and also helps to find potential quality problems of the capacitor in time, thereby optimizing the production process and improving the product quality.

[0064] Optionally, the set Faraday law and the water electrolysis reaction rule obtain the water content in the dielectric layer according to the total electric quantity, including: An electrochemical equivalent of the water electrolysis reaction is obtained, and the electrochemical equivalent is the ratio of the molar mass of a substance to the Faraday constant and the valence of the substance; According to the total electric quantity and the electrochemical equivalent, the mass of the water electrolysis in the dielectric layer is generated; According to the mass of the water electrolysis in the dielectric layer, the water content in the dielectric layer is obtained.

[0065] Specifically, first, the electrochemical equivalent of the water electrolysis reaction is obtained. The electrochemical equivalent is the ratio of the molar mass of a substance to the Faraday constant and the valence of the substance. In the water electrolysis reaction, 4 mol of electrons are transferred for the decomposition of 2 mol of water, so the number of electron transfers n corresponding to 1 mol of water is 2. The molar mass M of water is 18 g / mol, and the Faraday constant F is about 96485 C / mol. Thus, the electrochemical equivalent K = M / (F x n) can be calculated.

[0066] According to the total electric quantity and the electrochemical equivalent, the mass of the electrolyzed water in the dielectric layer is calculated. The total electric quantity Q is obtained by integrating the curve of the excess current changing with time. According to Faraday's law, the mass m of the electrolyzed water is related to the total electric quantity Q as m = K x Q. The calculated electrochemical equivalent K is substituted into the formula to obtain the mass m of the electrolyzed water. According to the mass of the electrolyzed water in the dielectric layer, the water content of the dielectric layer is obtained. The water content of the dielectric layer can be expressed as a mass fraction, i.e., the percentage of the mass of water to the total mass of the dielectric layer. By measuring or presetting the total mass of the dielectric layer, combined with the calculated mass of the electrolyzed water, the water content of the dielectric layer can be obtained.

[0067] In this optional embodiment, by obtaining the electrochemical equivalent of the water electrolysis reaction, a quantitative relationship between the total electric quantity and the mass of the electrolyzed water is established, thereby realizing the accurate calculation of the water content of the dielectric layer. First, the electrochemical equivalent is calculated by comprehensively considering the molar mass of water, the Faraday constant, and the number of electron transfers in the reaction, and the accuracy of the electrochemical equivalent is ensured based on the chemical reaction equation of the electrolyzed water. Then, the mass of the electrolyzed water is calculated using the total electric quantity and the electrochemical equivalent. This calculation process directly applies Faraday's law of electrolysis, providing a scientific basis for the quantitative analysis of the water content of the dielectric layer. On this basis, the water content of the dielectric layer is obtained by the ratio of the mass of the electrolyzed water to the total mass of the dielectric layer, realizing the accurate quantification of the water content.

[0068] Optionally, the obtaining of the leakage current characteristic of the capacitor according to the morphological feature of the cyclic voltammogram and the water content comprises: determining whether the capacitor has an abnormal leakage current characteristic according to the morphological feature of the cyclic voltammogram, wherein the morphological feature comprises an abnormal current peak, and the abnormal current peak comprises an asymmetric peak and a redox current peak; if the cyclic voltammogram has the asymmetric peak or the redox current peak, it is determined that the capacitor has an abnormal leakage current characteristic; if the cyclic voltammogram is approximately rectangular and does not have the asymmetric peak and the redox current peak, the water content is compared with a preset water content threshold value; if the water content exceeds the preset water content threshold value, it is determined that the capacitor has an abnormal leakage current characteristic; If the water content is within the preset water content threshold range, it is determined that the leakage current characteristic of the capacitor is normal.

[0069] Specifically, first, the overall shape of the curve is analyzed. Normally, the cyclic voltammetry curve of a good capacitor should be approximately rectangular, as shown in Figure 2 , and there are no obvious asymmetric peaks or redox current peaks. The rectangular shape reflects the ideal behavior of the capacitor during charging and discharging, i.e., the current and potential change linearly, and no additional chemical reactions occur.

[0070] When asymmetric peaks or redox current peaks appear in the curve, it indicates that additional electrochemical reactions occur at a certain potential, which may be related to moisture or other defects in the dielectric layer. According to these morphological characteristics, the presence of abnormal leakage current characteristics of the capacitor can be directly determined. If the cyclic voltammetry curve is approximately rectangular and no asymmetric peaks and redox current peaks are found, further judgment is made according to the water content. The measured water content is compared with the preset water content threshold. The preset water content threshold is determined according to the design standards and reliability requirements of the capacitor. Exceeding this value means that the moisture in the dielectric layer may have an adverse effect on the performance of the capacitor. If the water content exceeds the preset threshold, it is determined that the leakage current characteristic of the capacitor is abnormal, because excessive moisture may cause an increase in leakage current and reduce the insulation performance of the capacitor.

[0071] If the water content is within the preset water content threshold range, it is determined that the leakage current characteristic of the capacitor is normal, which indicates that the water content in the dielectric layer of the capacitor is within a controllable range and will not significantly affect its leakage current characteristic. In this case, the performance of the capacitor meets the design requirements and can be considered as a good product. By combining the morphological characteristics of the cyclic voltammetry curve and the water content analysis, the leakage current characteristic of the capacitor can be comprehensively and accurately evaluated, ensuring that only products meeting the standards can pass quality control, thereby improving the overall reliability of the product.

[0072] In a preferred embodiment of the present application, a periodic potential scan is applied to the electrodes of the laminated aluminum solid-state capacitor through cyclic voltammetry testing, and the current response of the electrodes at different potentials is recorded. On the one hand, the CV curve formed by a normal good product is approximately rectangular, as shown in Figure 2On the other hand, the relationship between the electrode charge and the mass of the water reaction substance in the dielectric layer during the electrolysis process is calculated by Faraday's law; when the Faraday process occurs at the electrode interface, there is a strict quantitative relationship between the amount of electricity passed and the mass of the reaction substance. When a specific potential scan is applied to the laminated aluminum capacitor anode, if there is adsorbed water in the dielectric layer, water molecules will undergo electrolysis near the theoretical decomposition voltage of about 1.23V. The total amount of electricity consumed by the electrolysis of water can be obtained by integrating the excess current, and then the corresponding water content in the dielectric layer can be calculated according to Faraday's law. By analyzing the water decomposition excess current in the CV curve, the water content can be quickly quantified, and finally the capacitor leakage current reliability state can be evaluated synchronously and non-destructively through fast C-V scanning, which provides a breakthrough detection method for improving product quality and reliability design. Specifically: The mass (m) of the substance deposited or dissolved on the electrode is proportional to the amount of electricity (Q) passed:

[0073] Where K is the electrochemical equivalent (the amount of electricity corresponding to a unit mass), I is the current intensity, and t is the time of electricity. By integrating the excess current with respect to time to calculate the total amount of electricity Q, the total amount of water electrolyzed in this process can be obtained: ; ; Where M: the molar mass of the substance (unit: g / mol); n: the valence of the substance (the number of electrons transferred in the electrode reaction); F: Faraday's constant (about 96485 C / mol).

[0074] The total reaction of electrolysis of water is: ; Each decomposition of 2 mol of water requires the transfer of 4 mol of electrons, and each mol of water corresponds to n=2 electrons. According to the above calculation, the total amount of water electrolyzed in this process can be obtained This embodiment provides a new idea for capacitor humidity evaluation based on the cyclic voltammetry principle of electrochemical analysis. Not only does it provide an efficient and accurate new method for quality control of laminated aluminum solid-state capacitors, but it can also be extended to reliability evaluation of other humidity-sensitive electronic components, and provides a quantitative basis for packaging process improvement, with significant technical and economic value and application prospects.

[0075] In this optional embodiment, the precise judgment of the capacitor leakage current characteristics is realized by combining the morphological characteristics of cyclic voltammetry curves and the moisture content. Through the analysis of the cyclic voltammetry curves, it can be quickly identified whether there is an abnormal electrochemical reaction in the capacitor. The existence of asymmetric peaks or redox current peaks in the curve is a direct indicator of the possible existence of additional chemical reactions inside the capacitor. These abnormal characteristics are usually related to defects in the dielectric layer or excessive moisture content. When the cyclic voltammetry curve presents an approximate rectangle and no obvious abnormal current peak, it means that the capacitor behaves normally during the charging and discharging process. At this time, further quantitative analysis of the moisture content is carried out to confirm whether its leakage current characteristics are normal. Comparing the measured moisture content with the preset threshold value can accurately determine whether the moisture in the dielectric layer is within a controllable range. If the moisture content exceeds the threshold value, it may trigger an electrochemical side reaction, increase the leakage current, and affect the insulation performance and reliability of the capacitor. Conversely, if the moisture content is within the threshold range, it indicates that the leakage current characteristics of the capacitor are normal and meet the quality standards. This combined morphological characteristic and quantitative analysis method of the embodiment not only improves the accuracy of the detection, but also provides a scientific basis for the optimization of the production process and quality control of the capacitor, which helps to improve the overall performance and market competitiveness of the product.

[0076] Optionally, the connecting the capacitor to the electrochemical workstation comprises: connecting the anode pin of the capacitor to the working electrode interface of the electrochemical workstation, and connecting the cathode pin of the capacitor to the counter electrode interface of the electrochemical workstation.

[0077] In this optional embodiment, first, the anode pin of the capacitor is connected to the working electrode (WE) interface of the electrochemical workstation through a wire, and it is ensured that the wire has good conductivity and the connection is firm to ensure stable transmission of current during the test. Then, the cathode pin of the capacitor is connected to the counter electrode (CE) interface of the electrochemical workstation through another wire. Similarly, the connection of the cathode pin also needs to ensure good conductivity and reliability of the connection to avoid test errors caused by poor contact.

[0078] After the connection of the anode and the cathode is completed, the connection between the electrodes is checked using a multimeter to ensure that there is no leakage contact between the electrodes, thereby ensuring the electrical isolation of the test system and the accuracy of the subsequent test. Through such a connection method, it can be ensured that the electrochemical workstation can accurately apply potential to the capacitor and accurately measure its current response.

[0079] In summary, the specific steps of the embodiment of the application are as follows: Step 1: Test system setup and electrode connection. First, place the sample of the laminated aluminum solid-state capacitor to be tested in a constant temperature and humidity environment (temperature 25 ± 2°C, humidity 60 ± 5% RH) for 30 minutes to eliminate short-term environmental factors that interfere with the moisture distribution in the dielectric layer. Then, complete the test system connection according to the electrode interface definition of the electrochemical workstation, connect the anode pin (usually the positive electrode) of the capacitor to the working electrode (WE) interface of CHI660E through a wire, and connect the cathode pin (negative electrode) to the counter electrode (CE) interface. After the connection is completed, use a multimeter to confirm that there is no leakage contact between the electrodes, and ensure the electrical isolation of the test system.

[0080] Step 2: Cyclic voltammetry (C-V) mode parameter setting and test execution. Switch the electrochemical workstation to C-V test mode, and set the following key parameters according to the characteristics of the dielectric layer water electrolysis reaction and the actual working scenario of the aluminum capacitor: (1) Voltage scan range: 0~10V, starting at 0V helps to observe the complete electrochemical behavior from zero bias. The high potential is set to 10V. This potential is higher than the theoretical decomposition potential of water (about 1.23V vs. RHE, the specific value in the aluminum oxide system needs to be calibrated, usually above 2-3V), to ensure that the water electrolysis Faraday current peak can be fully excited and observed; at the same time, 10V also covers the typical working voltage range of the capacitor, which is beneficial to evaluate its behavior under high field strength. (2) Scan rate: 0.5V / s, the choice of scan rate needs to balance signal resolution and test efficiency. Too fast scan rate (such as >1V / s) will cause the electrode surface reaction kinetics to lag, and the excess current peak of water electrolysis will be broadened or submerged in the background current; too slow scan rate (such as <0.2V / s) will prolong the test time and increase the influence of environmental interference (such as humidity fluctuations) on the results. With a scan rate of 0.5V / s, the C-V scan time can be controlled to be the shortest while ensuring the integrity of the water electrolysis current peak, effectively suppressing environmental noise. (3) Number of cycles, set to 5 cycles (10 scans in total), the first cycle is mainly used to activate the adsorbed water and defect sites on the surface of the dielectric layer, and the water electrolysis reaction tends to be stable in the subsequent cycles, so the C-V curves of the 2nd to 5th cycles are taken for water content calculation to exclude the irreversible activation effect of the first cycle.

[0081] After starting the test, the electrochemical workstation automatically applies a periodic triangular potential scan (from 0V to 10V, and then reversely scans to 0V), and simultaneously records the current response at different potentials to generate the C-V curve. During the test, real-time monitoring of the current signal is performed to determine whether there are abnormal fluctuations (such as sudden jumps or drifts), and if abnormalities are found, the test is paused and the electrode connection or environmental interference problem is checked Step 3: I-T mode characteristic observation and data saving, after completing the C-V scan, switch to the I-T (current-time) test mode to observe the excess current caused by water electrolysis and its decay behavior.

[0082] The specific operation is as follows: (1) Constant potential bias setting: apply a constant potential at the water electrolysis characteristic potential point identified by CV. (2) Observe the steady-state current: record the current-time curve at the constant potential for a long time. (3) Separate the current components: help to more clearly separate and quantitatively analyze, the non-faradic current is mainly the double-layer charging current and ohmic leakage current, which will quickly decay to a relatively stable platform value after applying a constant potential. The faradic current is generated by the continuous water decomposition reaction, which is manifested as a relatively stable "excess current" superimposed on the non-faradic current platform. Charge-discharge current analysis, in the positive scan (charging) and reverse scan (discharging) phase of the CV curve, respectively extract the charge-discharge current data. The charge-discharge current of a normal capacitor should be symmetrical, while the asymmetric current caused by water electrolysis can be used as a criterion for the presence of water.

[0083] After the test is completed, the C-V curve original data (potential-current array) and I-T curve data (time-current array) are exported through the CHI660E supporting software (such as CHI660E Data Analysis) and saved in Excel or TXT format for future use.

[0084] Step 4: Data processing and result analysis, (1) C-V curve water content quantitative calculation: extract the water electrolysis excess current (ΔI) from the C-V curve. The specific method is to calculate the current difference between the forward scan (anodic electrolysis) and the reverse scan (cathodic electrolysis), and subtract the aluminum substrate background current (marked by testing a blank aluminum piece) to obtain the excess current ΔI caused only by water electrolysis. According to the Faraday's law of electrolysis, by integrating the change of excess current ΔI with time, Q can be calculated, and then the dielectric layer water content (mass fraction) can be deduced. (2) Good product determination: quickly screen good products by comparing the CV curve shape (rectangular degree), water content and leakage current value thresholds. For example, if the CV curve shows an asymmetric peak or the water content exceeds the design standard, it is determined as a defective product. (3) Process improvement: optimize the dielectric layer preparation process (such as aluminum oxide film thickness, drying temperature, etc.) based on the relationship model between water content and leakage current to reduce water residue and improve capacitor reliability.

[0085] This embodiment realizes the rapid quantitative characterization of dielectric layer water content and in-situ correlation analysis of leakage current characteristics through the cooperation of C-V and I-T modes, providing standardized and non-destructive key technical support for process control, reliability prediction and failure analysis of laminated aluminum solid-state capacitors.

[0086] For example, a good capacitor that meets design specifications is characterized by an approximately rectangular cyclic volt-ampere (CV) curve, such as... Figure 2 As shown, the horizontal axis (Potential) represents potential, in volts (V). It reflects the voltage change applied to the capacitor by the electrochemical workstation during cyclic voltammetry testing. The potential starts at 0V, gradually increases to 10V (forward scan), and then decreases back to 0V (reverse scan), forming a complete cycle. This potential change is used to drive electrochemical reactions in the capacitor, particularly for detecting the electrolytic reaction of moisture in the dielectric layer. The vertical axis (Current / 1e-5A) represents current, in amperes (A), but current values ​​in the graph are expressed in 1×10⁻⁵ A increments. -5 The display is scaled down to units of A (i.e., 10 microamps, μA). Current is a measure of the flow of electrons in an electrochemical reaction. In cyclic voltammetry, the current response reflects the electrochemical behavior of a capacitor at different potentials.

[0087] For example, when the potential reaches near the decomposition voltage of water, if moisture is present in the dielectric layer, excess current will occur due to water electrolysis. For a good capacitor that meets design specifications, its cyclic voltammetry (CV) curve is approximately rectangular. This means that the capacitor exhibits ideal double-layer capacitance behavior during charging and discharging, without obvious redox peaks or other abnormal current peaks. This rectangular characteristic of the curve indicates that the capacitor's dielectric layer is intact, with no significant leakage current or electrochemical side reactions, demonstrating good insulation performance and electrochemical stability. Conversely, if unexpected electrochemical side reactions exist inside the capacitor, redox peaks will appear on the CV curve, the CV curve will deviate significantly from the rectangular characteristic, and identifiable redox current peaks will appear in a specific potential range. Therefore, by analyzing the geometric characteristics of the CV curve and the presence of abnormal current peaks, rapid and non-destructive reliability screening of capacitors can be achieved, effectively identifying defective products with potential failure risks.

[0088] For capacitors that have been stored in an atmospheric environment for a long time without undergoing a pre-baking process, CV testing was performed. During the initial cyclic voltammetry measurement, a significantly higher current than the charging current began to appear above 1V. Figure 3 As shown in curve 1, the excess current rises rapidly with increasing voltage (the decomposition voltage of water is 1.23V), but as the number of cycles increases, the peak value of the excess current decreases rapidly and eventually stabilizes. Figure 3 Curve No. 10 and Figure 4 As shown. Comparing the results before and after cyclic voltammetry, it was found that the leakage current decreased during the cyclic voltammetry process. This is because the moisture in the dielectric layer is electrolyzed when it exceeds the decomposition voltage. As it is continuously consumed, the excess current decreases continuously, thus reducing the leakage current. This is also equivalent to the effect when the capacitor fails during initial use without pre-baking.

[0089] Charge-discharge current Figure 4 As shown in the I-T curve in the process of electrolyzing water, the dark gray part (i.e., the part corresponding to Charge-discharge current in the figure) is the charge-discharge current, and the light gray part (i.e., the part corresponding to Excess current in the figure) is the excess current. H2O =8.4×10 -5 (g) Charge-discharge current Figure 5 As shown in the I-T curve in the process of electrolyzing water, the dark gray part (i.e., the part corresponding to Charge-discharge current in the figure) is the charge-discharge current, and the light gray part (i.e., the part corresponding to Excess current in the figure) is the excess current. The memory is used for storing a computer program. The processor is used for realizing the dielectric layer moisture content-leakage current collaborative analysis method as described above when the computer program is executed.

[0090] The dielectric layer moisture content-leakage current collaborative analysis system of the present application has the same advantages as the dielectric layer moisture content-leakage current collaborative analysis method of the present application compared with the prior art, and thus will not be described here again.

[0091] The computer readable storage medium of the present application has the computer program stored thereon, and when the computer program is executed by the processor, the dielectric layer moisture content-leakage current collaborative analysis method as described above is realized.

[0092] The computer readable storage medium of the present application has the same advantages as the dielectric layer moisture content-leakage current collaborative analysis method of the present application compared with the prior art, and thus will not be described here again.

[0093] Although the present application is disclosed as above, the protection scope of the present application is not limited to this. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and these changes and modifications will all fall within the protection scope of the present application.

Claims

1. A method of dielectric layer moisture content-leakage current co-analysis, characterized in that, The application is applied to a test system comprising a capacitor and an electrochemical workstation, and the dielectric layer moisture content-leakage current collaborative analysis method comprises: After the capacitor to be tested is placed in a preset temperature and a preset humidity for a preset time length, the capacitor is connected with the electrochemical workstation; The working mode of the electrochemical workstation is switched to a cyclic voltammetry test mode, and then the capacitor is scanned by a periodic triangular wave potential according to preset test parameters, current response data of the capacitor at different potentials are obtained, and a cyclic voltammetry curve is generated according to the current response data; Excess current of the dielectric layer of the capacitor is extracted from the cyclic voltammetry curve, and total electric quantity is obtained by integrating the excess current-time curve; According to Faraday's law and electrolytic water reaction rules, the moisture content of the dielectric layer is obtained according to the total electric quantity; According to the morphological characteristics of the cyclic voltammetry curve and the moisture content, the leakage current characteristics of the capacitor are obtained.

2. The dielectric layer moisture content-leakage current co-analysis method according to claim 1, characterized in that, The scanning of the capacitor by the periodic triangular wave potential to obtain the current response data of the capacitor at different potentials comprises: The electrochemical workstation is started, and the capacitor is automatically subjected to triangular wave potential scanning according to a preset voltage scanning range, a preset scanning rate and a preset cycle number; The periodic triangular wave potential scanning is positively scanned from 0V to 10V and then reversely scanned to 0V to form a cycle, and in each cycle, the current response data of the capacitor at different potentials are obtained by the electrochemical workstation; The current response comprises charging current and discharging current of the capacitor in the process of positive scanning and reverse scanning; The triangular wave potential scanning is repeated until the preset cycle number is completed, and the current response data of the capacitor at different potentials are obtained.

3. The dielectric layer moisture content-leakage current co-analysis method according to claim 2, characterized in that, The preset test parameters comprise a preset voltage scanning range, a preset scanning rate and a preset cycle number of the electrochemical workstation; The preset voltage scanning range of the electrochemical workstation is 0-10V, the initial voltage is 0V and the terminal voltage is 10V; the preset scanning rate of the electrochemical workstation is 0.5V / s; and the preset cycle number of the electrochemical workstation is 5 cycles.

4. The dielectric layer moisture content-leakage current co-analysis method of claim 2, wherein, The cyclic voltammetry curve is generated according to the current response data, which comprises: The current response data are arranged in order of potential to form a current-potential data point set; The current-potential data point set is plotted in a two-dimensional coordinate system to generate the cyclic voltammetry curve with potential as the horizontal coordinate and current as the vertical coordinate.

5. The dielectric layer moisture content-leakage current co-analysis method according to claim 4, wherein, The excess current of the dielectric layer of the capacitor is extracted from the cyclic voltammetry curve, and the total electric quantity is obtained by integrating the excess current-time curve, which comprises: The reference current of the dielectric layer of the capacitor is determined according to the cyclic voltammetry curve; The excess current is obtained according to the difference between each current value in the current response data and the reference current; The excess current-time curve is divided into multiple time intervals; determining a time interval according to the time interval, and generating a product of the excess current and the time interval in each of the time intervals; adding the products of the excess current and the time interval in all the time intervals to obtain the total electric quantity.

6. The dielectric layer moisture content-leakage current co-analysis method according to claim 5, wherein, The set Faraday's law and the water electrolysis reaction rule, according to the total electric quantity, obtain the water content of the dielectric layer, including: obtaining the electrochemical equivalent of the water electrolysis reaction, the electrochemical equivalent is the ratio of the molar mass of the substance to the Faraday constant and the valence of the substance; generating the mass of the water electrolysis in the dielectric layer according to the total electric quantity and the electrochemical equivalent; obtaining the water content of the dielectric layer according to the mass of the water electrolysis in the dielectric layer.

7. The dielectric layer moisture content-leakage current co-analysis method according to claim 6, wherein, The according to the shape characteristics of the cyclic voltammetry curve and the water content, obtain the leakage current characteristics of the capacitor, including: determining whether the capacitor has abnormal leakage current characteristics according to the shape characteristics of the cyclic voltammetry curve, wherein the shape characteristics include abnormal current peaks, and the abnormal current peaks include asymmetric peaks and redox current peaks; if the cyclic voltammetry curve has the asymmetric peaks or the redox current peaks, it is determined that the capacitor has abnormal leakage current characteristics; if the cyclic voltammetry curve is approximately rectangular and does not have the asymmetric peaks and the redox current peaks, comparing the water content with a preset water content threshold value; if the water content exceeds the preset water content threshold value, it is determined that the capacitor has abnormal leakage current characteristics; if the water content is within the preset water content threshold value, it is determined that the capacitor has normal leakage current characteristics.

8. The dielectric layer moisture content-leakage current co-analysis method of claim 1, wherein, The connecting the capacitor to the electrochemical workstation includes: connecting the anode pin of the capacitor to the working electrode interface of the electrochemical workstation, and connecting the cathode pin of the capacitor to the counter electrode interface of the electrochemical workstation.

9. A dielectric layer moisture content-leakage current co-analyzer system, characterized by, including a memory and a processor; The memory is used to store a computer program; The processor is used to implement the dielectric layer water content-leakage current collaborative analysis method according to any one of claims 1 to 8 when executing the computer program.

10. A computer-readable storage medium, characterized in that, The storage medium has a computer program stored thereon, and when the computer program is executed by the processor, the dielectric layer water content-leakage current collaborative analysis method according to any one of claims 1 to 8 is implemented.

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