Highly protected potted button supercapacitor and preparation method thereof

Abstract

The present application relates to the technical field of supercapacitor, and discloses a high-protection type potting button supercapacitor and a preparation method, which comprises a potting supercapacitor cell, an integrated nonvolatile memory, calibration data representing the individualized relationship between the electrical characteristics of the cell and temperature after the cell experiences potting, and a thermal transient response fingerprint obtained by using the calibration data as a reference, wherein the fingerprint is used to represent the integrity of the packaging interface, the potting damage process leading to the performance parameter discretization is converted into an informationized individual calibration process, the double capabilities of self-performance description and physical health authentication of the capacitor are improved, and the reliability of the device in the whole life cycle is improved.

Description

Technical Field

[0001] This invention relates to a highly protected potted button-type supercapacitor and its preparation method, belonging to the field of supercapacitor technology. Background Technology

[0002] Currently, in applications such as aerospace or critical industrial control systems, button-type supercapacitors are used as instantaneous power sources or backup power supplies, and their long-term operational stability is of paramount importance. To withstand harsh environmental factors such as vibration, shock, and humidity, encapsulating supercapacitors with epoxy resin or similar materials is a common technique in the industry to improve the mechanical strength and environmental tolerance of components.

[0003] However, the potting process itself is a physical process accompanied by thermo-coupling effects. The potting material shrinks in volume during curing, and its coefficient of thermal expansion is usually different from that of the capacitor's metal casing. This means that during the cooling from the curing high temperature to room temperature and subsequent operating temperature cycles, the potting body will inevitably exert a long-term, irreversible mechanical stress on the capacitor cell. This stress acts directly on the internal structure of the capacitor, improving external protection capabilities while also altering the microscopic characteristics of the electrode-electrolyte interface. The direct consequence is that the capacitor's key electrical parameters, especially the equivalent series resistance (ESR) and capacitance, will permanently deviate from their initial calibration values ​​before potting.

[0004] Furthermore, the parameter shifts caused by potting stress are not uniform or predictable fixed values, but rather have a unique impact on each individual capacitor. This causes products from the same batch with highly consistent performance to become a discrete group with vastly different electrical characteristics after potting. Using low-stress potting materials can only alleviate this problem, but cannot fundamentally eliminate the stress caused by differences in material physical properties. Moreover, screening electrical parameters at room temperature after potting cannot capture the complex, nonlinear, and novel dependence of this parameter shift on temperature. Specifically, existing technologies face a technical conflict here: 1. The potting process, which ensures the mechanical protection of the device, is directly constrained by the determinism of its electrical performance parameters; 2. The potting process transforms the electrical behavior of the device from a standard state to an individualized, unknown state, and the industry lacks an intrinsic method to accurately describe and quantify this individualized state after potting. Therefore, in the prior art, the actual performance parameters of a potted supercapacitor at its actual operating temperature cannot be accurately predicted. The system design heavily relies on the initial calibration parameters of the device and a wide design margin, which introduces uncertainty in high-reliability applications. How to obtain and apply the unique temperature-related electrical characteristics of each potted component, and transform a manufacturing process that introduces uncertainty into a process that provides deterministic data, becomes the technical problem to be solved by this invention. Summary of the Invention

[0005] This invention provides a high-protection potted button-type supercapacitor and its preparation method. Its main purpose is to solve the problem that the potting process causes unpredictable individual deviations in the performance parameters of supercapacitors, resulting in a lack of deterministic understanding of their electrical behavior at real operating temperatures.

[0006] To achieve the above objectives, the present invention provides a high-protection potted button-type supercapacitor, comprising: a potted supercapacitor cell; a non-volatile memory integrated with the supercapacitor cell; the non-volatile memory storing a set of calibration data and a thermal transient response fingerprint; the calibration data being an individualized functional relationship between the equivalent series resistance and temperature of the supercapacitor cell after undergoing the potting process; and the thermal transient response fingerprint being a characteristic parameter characterizing the integrity of the encapsulation interface between the supercapacitor cell and the potting encapsulation, which is obtained by monitoring the thermal relaxation process of the equivalent series resistance after applying an electrical pulse of known energy to the supercapacitor cell, using the calibration data as a temperature reference.

[0007] Preferably, the calibration data is stored in non-volatile memory in the form of a set of polynomial coefficients describing individualized functional relationships, or a lookup table for indexing individualized functional relationships, and the thermal transient response fingerprint is a characteristic time constant of the decay of the equivalent series resistance during thermal relaxation.

[0008] Preferably, the thermal transient response fingerprint is further defined as a differential index, which is obtained by comparing the characteristic time constant of the supercapacitor cell after it is encapsulated with the initial characteristic time constant of the supercapacitor cell before it is encapsulated, in order to offset the influence of environmental factors on the integrity judgment of the encapsulation interface.

[0009] Preferably, the acquisition of thermal transient response fingerprints follows these internal rules: through a functional relationship defined by calibration data. inverse function The equivalent series resistance monitored during thermal relaxation The sequence is converted into an internal temperature. The decay sequence is obtained, and the thermal transient response fingerprint is extracted based on the decay sequence of the internal temperature, where, This is the time after the thermal excitation ends.

[0010] Preferably, the calibration data stored in the non-volatile memory is also used to characterize a second integrated function relationship between the reactance and temperature of the supercapacitor cell; the equivalent series resistance and reactance together constitute a two-dimensional initial state space, which is configured to distinguish whether the performance degradation of the supercapacitor is due to the physical stress effect of initial curing or the effect of subsequent electrochemical aging during its service life.

[0011] Preferably, the calibration data and thermal transient response fingerprint stored in the non-volatile memory are both obtained by performing matched filtering on the original monitoring signal. The matched filtering is performed based on the expected signal shape that the original monitoring signal should theoretically have, in order to suppress electromagnetic interference noise in the industrial manufacturing environment.

[0012] Preferably, the non-volatile memory also stores a quality control flag bit, which is used to indicate the acquisition of calibration data and thermal transient response fingerprint. This quality control flag bit is executed only after the electrical contact integrity between the pre-diagnostic confirmation test system and the supercapacitor cell meets the preset conditions. The pre-diagnostic test is based on the spectrum analysis of the baseline electrical noise signal of the supercapacitor cell in steady state and the determination of whether the energy of its low-frequency noise component is lower than the preset threshold.

[0013] Preferably, the thermal transient response fingerprint is a feature vector, which is extracted by morphological analysis of the complete decay curve of the equivalent series resistance during the thermal relaxation process. The morphological analysis includes multi-exponential function fitting or multi-moment analysis of the complete decay curve to obtain multiple morphological feature parameters for identifying the defect mode of the packaging interface. The feature vector is configured to be matched with a preset defect fingerprint library to output a classifiable defect mode diagnosis result.

[0014] Preferably, the non-volatile memory is connected to the external pins of the supercapacitor cell via a serial communication interface, allowing an external power management system to read calibration data and thermal transient response fingerprints, and to accurately calculate the instantaneous output power and health status of the supercapacitor based on the calibration data.

[0015] A method for preparing a high-protection potted button-type supercapacitor includes the following steps: Step a, during the entire thermodynamic process of potting, curing and cooling a supercapacitor cell, the equivalent series resistance of the supercapacitor cell is monitored in situ to obtain performance evolution data, and based on the performance evolution data, calibration data characterizing the individualized functional relationship between the equivalent series resistance and temperature of the supercapacitor cell after undergoing the potting process is generated.

[0016] Step b: After generating calibration data, an electrical pulse of known energy is applied to the supercapacitor cell to generate thermal excitation. The calibration data generated in step a is used as a temperature reference to monitor the thermal relaxation process of the equivalent series resistance of the supercapacitor cell, so as to extract a thermal transient response fingerprint to characterize the integrity of the encapsulation interface between the supercapacitor cell and the potting package.

[0017] Step c: Store the calibration data and thermal transient response fingerprint in a non-volatile memory integrated with the supercapacitor cell.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By continuously monitoring the electrical characteristic parameters of the supercapacitor in situ during the complete thermodynamic process of potting, curing and cooling, a set of functional relationships reflecting the evolution of the electrical characteristics of the individual capacitor with temperature after being subjected to real and irreversible physical stress is obtained; by storing this set of calibration data characterizing the individual electrical personality in a non-volatile memory associated with the capacitor, the passive device, whose performance parameters are discretized due to manufacturing stress and whose electrical behavior is unpredictable in subsequent applications, is transformed into an energy storage element carrying a precise and personalized performance description. The application system can thus obtain a deterministic understanding of its key performance parameters within the entire operating temperature range of the device, avoiding the risks arising from relying on general models for estimation.

[0019] 2. By simultaneously monitoring at least two electrical characteristic parameters with different sensitivities to different physical aging mechanisms during the in-situ monitoring step, such as equivalent series resistance and reactance, the generated calibration data is no longer a temperature curve of a single parameter, but constitutes a multi-dimensional initial state characteristic spectrum. When the device's performance changes after long-term service, the application system can project the real-time measured multi-dimensional parameters onto this initial spectrum, thereby establishing an analytical framework to distinguish whether the performance degradation is due to the physical stress of initial curing or the effects of subsequent electrochemical aging, providing a theoretical basis for the predictive health management of the device.

[0020] 3. After completing the calibration data storage, a package interface integrity quality inspection step is also included. This step uses an existing test system to apply a predicted electrical pulse to the capacitor as an internal thermal excitation, and uses the functional relationship between the electrical parameters and temperature that have been precisely calibrated in the main scheme. By continuously monitoring the decay process of these parameters after excitation, the relaxation characteristics of heat conduction from the inside of the device to the outside are characterized. This method transforms a purely mechanical structural defect of the package interface that is invisible in conventional electrical testing into a thermal relaxation characteristic signal that can be measured instantly at the end of manufacturing. This allows for the identification and elimination of individuals with long-term thermal management risks before the product leaves the factory, ensuring the thermal stability and reliability of the device throughout its entire life cycle. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the preparation process of the present invention, which synchronizes physical packaging and information calibration.

[0022] Figure 2 This is a schematic diagram of the encapsulated supercapacitor structure integrating non-volatile memory according to the present invention.

[0023] Figure 3 This is a timing diagram of electrical contact diagnosis based on baseline noise spectrum analysis according to the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0025] This invention relates to a high-protection potted button-type supercapacitor and its fabrication method, applicable to applications such as aerospace or critical industrial control where high long-term reliability of energy storage devices is required. In these applications, button-type supercapacitors are used as instantaneous power sources or backup power supplies, and their operating environment is often accompanied by vibration and temperature and humidity cycles. To ensure their structural stability, they are typically potted with materials such as epoxy resin. However, during the curing and cooling process, the potting material generates irreversible mechanical stress due to volume shrinkage and mismatch in thermal expansion coefficients. This stress acts on the supercapacitor cell, causing its equivalent series resistance (ESR) and other electrical parameters to deviate non-uniformly and unpredictably from their initial values ​​before potting. This makes existing systems that rely on general device models for power prediction risk failure under extreme conditions due to misinterpretations of the device's true performance. This method addresses this by physically potting... The sealing process is combined with individualized calibration and physical health certification via information technology, ensuring that each finished supercapacitor has personalized performance description data and encapsulation interface integrity data stored in its non-volatile memory. The fabrication method mainly includes three steps: First, under conditions throughout the entire thermodynamic process of sealing, in-situ electrical characteristic evolution is monitored to generate individualized calibration data; second, based on this calibration data as an internal temperature reference, active detection of encapsulation interface integrity is performed, and thermal transient response fingerprints are extracted; finally, the obtained calibration data and thermal transient response fingerprints are stored in a non-volatile memory integrated with the capacitor cell, completing the internalization of device data. The combination of these three steps constitutes a method for fabricating passive energy storage devices as energy storage devices that integrate non-volatile memory containing personalized performance data and physical health certification.

[0026] In one specific embodiment, the initial state of the method is defined as follows: the object of action is a supercapacitor cell to be encapsulated, characterized by its rated capacitance. Rated voltage At ambient temperature , frequency measurement The initial equivalent series resistance is not higher than The equipment used is an automated testing system that integrates a four-wire Kelvin test fixture, a wide-temperature-range programmable temperature control chamber, and an AC impedance analyzer. The temperature control accuracy of this system is no less than [specified value]. Impedance measurement accuracy is not lower than In step a, namely the in-situ monitoring and calibration data generation step, the potting stress not only causes a shift in the fixed value of ESR at room temperature but also reshapes its dependence on temperature, resulting in a large deviation in temperature extrapolation based on pre-potting parameters. To obtain an accurate dependence, this method monitors the equivalent series resistance of the supercapacitor cell in-situ throughout the entire thermodynamic process of potting, curing, and cooling to obtain its performance evolution data. The parameters of this thermodynamic process are set as a test cycle covering the device's operating limit temperature. For example, the capacitor with epoxy resin potting material is placed in a temperature-controlled chamber, starting from the initial room temperature... by The rate of heating to the curing temperature and keep warm Then, it is cooled to the low-temperature limit at the same rate. Finally, it will warm up to In this complete, approximately During the thermodynamic cycle, the AC impedance analyzer is used to... The temperature interval is the trigger condition, and the frequency point for automatic execution is 1. The system performs AC impedance measurements to acquire approximately 250 data point pairs, including temperature and equivalent series resistance. This set of data point pairs maps the functional relationship between the electrochemical characteristics of the specific capacitor and temperature after physical stress. Based on this performance evolution data, the system then generates calibration data characterizing the individualized functional relationship between the equivalent series resistance and temperature of the supercapacitor cell after the encapsulation process by performing polynomial fitting using the least squares method. For example, the acquired data point pairs are fitted to a second-order polynomial function. ,in, The temperature is in Celsius, and a set of polynomial coefficients specific to this individual capacitor is obtained, such as... This set of coefficients, or a lookup table generated by the function, constitutes the calibration data for the capacitor. It should be noted that, to obtain data for distinguishing performance degradation modes during device service, at least two electrical characteristic parameters with different sensitivities to different physical aging mechanisms are simultaneously monitored during the in-situ monitoring step. Specifically, during the... While performing ESR measurements, the AC impedance analyzer also measures at a mid-frequency point related to the charge transfer process, such as... Simultaneously measure the capacitor's reactance and generate a second integrated function relationship. The calibration data; since the physical stress of initial curing mainly affects the ion transport path and thus changes the ESR, while the subsequent electrochemical aging changes the electrode surface activity more and thus affects the reactance related to charge transfer, this two-dimensional initial state space composed of equivalent series resistance and reactance can be configured to analyze the sources of performance degradation of supercapacitors during their service life by projecting real-time measured parameter pairs into this initial state space.

[0027] In step b, the active detection step of the encapsulation interface integrity, micron-level delamination or air gaps that may occur between the potting resin and the capacitor's metal casing can form a high thermal resistance interface, hindering the dissipation of Joule heat from the device and posing a long-term thermal management risk. To detect this defect, this method, after generating calibration data, applies a predicted energy electrical pulse to the supercapacitor cell to generate thermal excitation. The procedure for this step is as follows: a programmable current source applies an amplitude of [missing value] to the capacitor. The duration is A rectangular current pulse, for a... The ESR value after potting is The capacitor, the Joule thermal energy injected by the pulse Immediately following the end of thermal excitation, the system uses the calibration data generated in step a as a temperature reference. The thermal relaxation process of the equivalent series resistance of the supercapacitor cell is continuously monitored with time resolution. This monitoring process utilizes the functional relationship defined in step a. inverse function The monitored equivalent series resistance The sequence is converted into an internal temperature. The decay sequence of the internal temperature is obtained, and a thermal transient response fingerprint is extracted based on this decay sequence to characterize the integrity of the encapsulation interface between the supercapacitor cell and the potting package; one form of this fingerprint is a characteristic time constant of the decay of the equivalent series resistance during thermal relaxation. The calibration process involves fitting the internal temperature decay sequence to a single exponential decay function. ,in, This represents the peak temperature rise after the pulse ends. This is the desired time constant. For a device with an intact package interface, its heat conduction path is unobstructed. Smaller values, for example However, in a device with interface delamination, heat dissipation is hindered. The value will increase, for example, reaching .

[0028] To enhance the robustness of this diagnostic method and mitigate the impact of environmental factors on the integrity assessment of the encapsulation interface, the thermal transient response fingerprint is further configured as a differential index. The operational procedure is adjusted by performing the aforementioned thermal transient response test once before encapsulating the supercapacitor cell to obtain its initial characteristic time constant in the exposed state. After potting and encapsulation, the same test was performed again to obtain the characteristic time constant of the encapsulated product. The thermal transient response fingerprint ultimately stored in memory is a differential index obtained by comparing the characteristic time constant of the supercapacitor cell after it has been encapsulated with the initial characteristic time constant of the supercapacitor cell before it was encapsulated. This differential processing can offset the impact of common-mode interference factors such as ambient temperature fluctuations or minor batch differences in materials on the measurement results. Furthermore, to identify defect modes, the thermal transient response fingerprint can be configured as a feature vector, the generation procedure of which is that the system does not convert the complete... Instead of simplifying the decay curve to a single time constant, morphological analysis is performed on it. An alternative approach is to fit the complete decay curve to a multi-exponential function, for example, fitting it as... , where the time constant Related to the diffusion characteristics of heat within the capacitor core, and the time constant This is related to the heat conduction characteristics through the encapsulation interface, by A feature vector composed of multiple morphological characteristic parameters is configured to be matched with a pre-set defect fingerprint database obtained through finite element simulation or measurement of known defect samples to output a categorizable defect pattern diagnosis result. In industrial manufacturing environments, electromagnetic interference is one of the factors affecting the measurement of weak signals. Therefore, the acquisition of calibration data and thermal transient response fingerprints can both be based on the results obtained after matched filtering of the original monitoring signal. The input of this processing procedure is the original monitoring signal with noise and a pre-built signal template based on the theoretical morphology of the signal. For example, for the thermal relaxation process, the template is a standard exponential decay curve. The core of the processing is to perform cross-correlation calculation between the acquired signal and the desired signal template. Since the actual decay signal is highly correlated with the template morphology, the calculation result will produce a sharp peak, while random electromagnetic interference noise unrelated to the template morphology will be suppressed. By analyzing the cross-correlation peak, the system can reconstruct a signal curve for subsequent parameter extraction.

[0029] Meanwhile, to avoid misjudgments caused by poor contact in the testing system itself, this method also includes a pre-diagnostic step to confirm the integrity of the electrical contact between the testing system and the supercapacitor cell. The challenge of this pre-diagnostic step is that a degraded test probe contact point is itself an unstable resistor, which can contaminate subsequent excitation and measurement processes, making it difficult for the system to distinguish whether the final abnormal result originates from a device defect or a test link failure. Therefore, before applying any electrical pulse, the system first acquires a data set for a period of time... The baseline electrical noise signal of the supercapacitor cell under steady state was obtained and subjected to Fast Fourier Transform (FFT) for spectral analysis. A healthy physical contact has a noise spectrum close to flat white noise, while an unstable contact will introduce... Flicker noise, therefore, the system determines its low-frequency noise components, such as... to The integrity of the electrical contact is determined by checking whether the integrated energy within the frequency band is below a preset threshold. Only after this pre-diagnostic confirmation that the test contact meets the preset conditions is the subsequent acquisition of calibration data and thermal transient response fingerprints performed. Furthermore, a quality control flag is stored in non-volatile memory to indicate the validity of this data acquisition. Finally, in step c, a standard... Alternatively, a serial communication interface such as SPI can be used to store the calibration data and thermal transient response fingerprint generated in the previous steps, which characterize the individual capacitor, into a non-volatile memory that is connected to and integrated with the external pins of the supercapacitor cell. This allows the external power management system to read the calibration data and thermal transient response fingerprint through the serial communication interface throughout the entire service life of the device, and to calculate the instantaneous output power and health status of the supercapacitor based on the individualized calibration data.

[0030] Example 1: In a deep space exploration mission, the power management system on the probe needs to be located at the end of the orbit, where the ambient temperature drops to... Under operating conditions, a highly protected potted button-type supercapacitor is controlled to provide a continuous power supply for the deployment mechanism of the high-gain antenna. Peak current is The power pulse; when using conventional potted capacitors, the system's built-in universal temperature-ESR model is based on its room temperature calibration parameters before potting. This model cannot account for the potting stress on the individual capacitor. The specific impact of ESR makes it impossible for the system to accurately determine the instantaneous power it can output at that time. If the actual ESR value is higher than the model prediction, the internal voltage drop during the pulse will exceed expectations, which may cause the terminal voltage supplied to the deployment mechanism to fall below its operating threshold, resulting in slow deployment or failure. In this embodiment, the supercapacitor used in the detector power management system integrates a non-volatile memory containing its individualized performance data. Before executing the antenna deployment command, the power management system first reads its thermal transient response fingerprint from the memory through its serial communication interface. This fingerprint is a differential index. Its value is Because this value is lower than the system's preset value, it indicates a risk of thermal management issues at the packaging interface. The system uses the threshold value to confirm that the integrity of the capacitor's encapsulation interface meets the preset conditions.

[0031] After confirming the integrity of the package, the power management system continues to read the calibration data of the individual capacitor from non-volatile memory. This data is a set of data describing the functional relationship. The polynomial coefficients are then used to determine the current operating temperature by acquiring readings from the adjacent temperature sensor. Then, substituting this temperature value into the above functional relationship, and using the capacitor's unique coefficients for calculation, the ESR value at this low temperature is obtained. The power management system is based on this The calculated ESR value for the upcoming A feasibility study of the discharge pulse was conducted, and the internal voltage drop during the pulse was calculated to be [value missing]. The capacitor's output voltage can be maintained above the working threshold of the deployment mechanism. Based on this, the system issues an execution command, the capacitor releases electrical energy, the high-gain antenna deploys to the predetermined working position, and the detector establishes a communication link with the ground command center. A manufacturing process that affects the physical characteristics of the component is combined with in-situ parameter monitoring that is carried out simultaneously in the process to characterize these effects. The obtained data on the individualized characteristics of the characterizing parameters are stored in the component itself, so that the status of the component in subsequent applications is known.

[0032] Example 2: To verify the effectiveness of the preparation method in individualized parameter characterization and packaging defect identification, the following experiment was conducted. The experimental platform consisted of a programmable temperature control chamber, an AC impedance analyzer, and a programmable current source. The temperature range of the programmable temperature control chamber was [temperature range missing]. to Temperature control stability is The AC impedance analyzer's measurement frequency range covers... to Its equivalent series resistance measurement accuracy is better than The output current accuracy of the programmable current source is: The time control resolution is The test subjects were 20 button-type supercapacitor cells from the same batch, with an initial nominal value of ,exist and The mean initial ESR measured under the given conditions is The 20 samples were randomly divided into three groups: sample group A (10 samples), sample group B (5 samples), and control group C (5 samples). Before potting, a small cavity with a diameter of [missing information] was placed between the bottom of the battery cell and the potting material in sample group B. Thickness is Circular polyimide sheets were used to simulate localized delamination defects at the encapsulation interface; all 20 samples used the same epoxy resin potting compound and were produced in the same batch, according to... Heat up to and maintain Then cool down to Then warm up to The same thermal process is used for curing.

[0033] For samples A and B of this invention, the test platform monitors them in situ during the curing and cooling process to generate their respective calibration data, i.e., functional relationships. The polynomial coefficients; after curing, thermal transient response fingerprint tests were performed on samples A and B of this invention. The selection of parameters for the thermal excitation pulse needs to balance the signal amplitude with the non-invasiveness of the test. This experiment uses... Duration The current pulse, for the potted ESR is approximately The sample, the injected heat is approximately The resulting internal temperature rise to Between these values, the temperature rise was within the safe operating range of the capacitor and provided a distinguishable signal amplitude for subsequent relaxation curve analysis; for control group C, the temperature rise only occurred after curing was completed. The final ESR value was measured using an AC impedance analyzer.

[0034] Table 1: Comparison of key test data for some samples in each sample group:

[0035] Test data, as shown in Table 1, indicate that after undergoing the same potting process, all samples exhibited [specific characteristics / performance]. The ESR values ​​under these conditions exhibit a discrete distribution, ranging from arrive The results show that the effect of potting stress is individualized and discrete; it should be noted that the samples with internal defects in sample group B of this invention... The ESR values ​​of the samples below overlap with those of intact samples in sample group A and control group C of this invention in terms of distribution range, making them indistinguishable by conventional room temperature electrical parameter screening; in contrast, thermal transient response fingerprints... They exhibit different distributions; all intact samples, i.e., sample group A of this invention, show different distributions. The values ​​are all in to Within the scope, and all samples with artificial implantation defects, namely sample group B of the present invention, The values ​​are all greater than This phenomenon is due to the artificially implanted polyimide sheet forming a high thermal resistance layer, which slows down the dissipation of Joule heat generated by the thermal excitation pulse from the capacitor core to the outside, thereby prolonging the thermal relaxation time. The experimental results show that the preparation method, through in-situ monitoring and modeling, can obtain the functional relationship between the electrical characteristics and temperature of each encapsulated supercapacitor. At the same time, the quality inspection step of its encapsulation interface integrity can identify samples with mechanical defects in the encapsulation interface through thermal transient response testing. Such samples are difficult to detect in conventional electrical tests. This method enables the data carried by the encapsulated device itself to characterize its individual performance and encapsulation health status.

[0036] Example 3: This example combines Figures 1 to 3 This section describes the high-protection potted button-type supercapacitor and its preparation method, such as... Figure 1As shown, the process begins with a supercapacitor cell to be encapsulated as input. It first enters a pre-diagnostic stage to verify the integrity of electrical contacts. After successful verification, the process proceeds to step a, namely, in-situ monitoring and calibration data generation. This step monitors the entire thermodynamic process to obtain individualized electrochemical characteristics. A key module in this step is the simultaneous monitoring of two parameters: equivalent series resistance (ESR) and reactance, to construct a two-dimensional initial state space. Subsequently, the process enters step b, namely, active detection and fingerprint feature extraction. By applying electrical pulse excitation and monitoring the thermal relaxation process, the integrity of the encapsulation interface is characterized. Finally, in step c, data internalization and integration are performed, storing the calibration data and thermal transient response fingerprint obtained in the previous steps into non-volatile memory, thereby outputting a finished supercapacitor product integrating individualized performance data and physical health certification.

[0037] like Figure 2 As shown, the core of this capacitor is a supercapacitor cell with its positive and negative terminals led out. This cell, along with a non-volatile memory, is encapsulated within a housing consisting of a metal top cover and a metal base, filled with potting materials such as epoxy resin. The enlarged view of the encapsulation interface clearly shows the relative positions of the metal casing, potting material, and cell. The non-volatile memory is connected via a... The serial communication interface is connected to the external system via the SDA and SCL pins. Its internal storage includes a thermal transient response fingerprint for characterizing the integrity of the package interface, and a quality control flag. At the same time, externally input calibration data, namely the ESR(T) function characterizing the relationship between equivalent series resistance and temperature and the reactance(T) function characterizing the relationship between reactance and temperature, are also stored in this memory.

[0038] like Figure 3 As shown, this process involves five logical units: a quality control system, a test probe, a capacitor, a spectrum analyzer, and a judgment module. The process begins with the quality control system issuing an initial contact command to the test probe. The test probe then establishes an electrical connection with the capacitor and starts noise acquisition. The test probe continuously acquires baseline noise from the capacitor for, for example, 100ms, and returns the acquired electrical noise signal to the spectrum analyzer. The spectrum analyzer performs FFT spectrum analysis on the data and transmits the obtained low-frequency noise energy value to the judgment module. The judgment module compares the energy value with a preset threshold. If the contact is good, the judgment module returns a pass signal to the upstream diagnostic stage, and the quality control system continues subsequent tests. If the contact is poor, the judgment module triggers a probe check alarm to the quality control system, indicating that the contact needs to be readjusted.

[0039] Example 4: This example provides an engineering calibration and implementation procedure for a technical solution that uses morphological analysis to extract thermal transient response fingerprints to identify packaging interface defect patterns. In a quality control application for mass production of high-protection potted button-type supercapacitors, this is achieved by measuring a single characteristic time constant. While samples with encapsulation defects can be detected, the physical patterns of these defects cannot be classified. When production line defect rates fluctuate, process engineers lack data to determine whether the root cause is uneven mixing of the potting compound or improper mold pressing, among other specific failure modes. To establish the correlation between thermal relaxation curve morphology and physical defect patterns, an offline defect fingerprint library calibration procedure was executed. The initial state of this procedure was defined as follows: the target samples were 30 unencapsulated supercapacitor cells from the same batch as the production line products, divided into three groups: Group A (10 cells) as intact samples, Group B (10 cells) for simulating center delamination defects, and Group C (10 cells) for simulating edge air gap defects. Before encapsulation, a diameter [missing information] was placed at the center of the bottom of the metal casing of the Group B samples. The circular polyimide sheet, in group C, was prepared by temporarily inserting a rod with a diameter of [missing information] at the edge joint between the metal shell and the mold after potting and encapsulation. The metal wire is pulled out after the potting compound has initially solidified to form a channel defect at the edge; the equipment environment used is the automated testing system used in the aforementioned embodiments.

[0040] The calibration procedure involves applying the same potting and curing process to all 30 samples in the three groups mentioned above. Subsequently, the aforementioned thermal transient response fingerprint test is performed on each sample. The test system records the results after the excitation pulse ends. Internal equivalent series resistance The decay sequence is then converted into an internal temperature decay sequence using the obtained individualized calibration data. A software analysis module analyzes each... The decay curve was fitted to a double exponential decay model using the nonlinear least squares method. From the fitting results, a feature vector consisting of three morphological feature parameters is extracted for each sample. ,in, For rapid decay time constant, The time constant is the slow decay time constant, while The ratio of the two amplitudes Statistical analysis was performed on the feature vectors of 30 calibrated samples. Samples with different defect patterns exhibited a clustered distribution in the three-dimensional feature space. The features of intact samples (Group A) were as follows: Smaller value and The value is relatively large, and the characteristics of the central delamination sample (Group B) are: The value increases but The values ​​did not change significantly, while the edge air gap samples (group C) were characterized by... The value did not change much, but Value and The values ​​all exhibit moderate variations; based on this, the center vector of each cluster is calculated, which is the average value of each component of the feature vector of each type of sample, thereby establishing a defect fingerprint database, in which the center vector of the intact pattern... The center vector of the central delamination mode Edge air gap mode center vector In production line testing applications, after a capacitor under test has completed potting and curing, the system also performs thermal transient response testing on it and extracts its feature vector. Subsequently, the system calculates the Euclidean distance between the test vector and each center vector in the defect fingerprint database, and classifies the test sample into the defect pattern with the smallest distance. If the calculation yields... and If the distance is the smallest, the system outputs a diagnostic result as a packaging defect: edge air gap. This classification result is recorded and used to guide the adjustment of the production process.

[0041] Example 5: This example describes the engineering calibration procedures for key quality control thresholds involved when the preparation method is applied to a production line. Before mass production on a newly built automated production line for high-protection potted button-type supercapacitors, it is necessary to set thermal transient response fingerprint thresholds for the testing system. Compared with baseline noise power threshold For calibration One hundred samples were randomly selected from the pilot production batch, and the complete preparation method was performed on these 100 samples to obtain their respective differential indices. Meanwhile, scanning acoustic microscopy was used to perform non-destructive testing on the internal structure of these 100 samples to confirm whether there were delamination or void defects at their encapsulation interfaces; the test results showed that 95 samples had no internal defects. The mean of the value distribution is The standard deviation is The remaining 5 samples had interface defects. The values ​​are all greater than ; The value of is set at six standard deviations above the mean of the intact sample distribution, i.e. This value is written into the control software of the testing system and used as a benchmark for judging product qualification.

[0042] For calibration The probes of the test fixture were welded to a known intact standard sample to create a low and stable contact resistance. Under this condition, the system continuously performed 1000 pre-diagnostic steps, acquiring steady-state baseline electrical noise signals and performing spectral analysis to calculate the low-frequency integrated power. The distribution of, with a mean of The standard deviation is Baseline noise power threshold The value is set at ten standard deviations above the mean of the noise base distribution, i.e. In the automated testing process, any sample If the measured value exceeds this threshold, the test will be deemed invalid and a probe check alarm will be triggered.

[0043] Example 6: This example illustrates the test parameter optimization and adaptive calibration procedures required when the preparation method is applied to different product models or when facing changes in the production line environment. In a production line with an existing testing system, when a new type of supercapacitor with different heat capacity and electrical characteristics is introduced, the procedure for determining its thermal excitation pulse parameters for this product model is as follows: Take 10 intact samples of the new model, and the testing system performs a parameter scan test on each sample once. This test applies a set of parameters with different current amplitudes. With duration The pulse matrix formed, in which the current The range of variation is to Step length Duration The range of variation is to Step length For each The system records the peak internal temperature rise generated by the combination. And the signal-to-noise ratio of the subsequent thermal relaxation curve Test system software in all aspects that meet Constraints In the combination, select the one that makes The largest set of parameters is used as the excitation parameters for this product model, and this set of parameters is... and This is set as part of the standard test procedure for this product model. The desired attenuation template used for matched filtering is configured to be updated periodically to adapt to minor changes in the production line environment or component batches. This procedure is executed before the start of each shift. The system selects 10 standard samples with stable physical properties for testing and collects their respective thermal relaxation curve data. The system uses wavelet transform to denoise these 10 curves to obtain 10 reference signals. Then, these 10 reference signals are averaged to generate an updated desired attenuation template. This updated template is loaded into the matched filtering module for electromagnetic interference noise suppression of all subsequent products in this shift.

[0044] This embodiment describes a procedure for differentiating the root causes of performance degradation in devices after long-term service using a two-dimensional initial state space; telemetry data from a supercapacitor prepared according to the method of this invention, after five years of in-orbit service, shows that... The ESR decreased by 30% compared to the factory value. To determine the dominant factor of this degradation, the ground system first retrieved the factory-calibrated two-dimensional initial state-space calibration data from the capacitor's non-volatile memory. This data defined two baseline curves. and The system instructs the capacitor to perform an on-orbit AC impedance measurement to obtain its current impedance. The measured values ​​below And project that point onto the and In a two-dimensional state change plane with the origin, the state change vector is obtained. ,in It should be noted that, based on electrochemical theory, in simple electrochemical aging, the direction of the state change vector is mainly along the reactance. The axial extension, coupled with the continuous deterioration of the initial stress, causes the direction of its state change vector to primarily follow the equivalent series resistance. Extend along the axis; calculate the state change vector. Based on the angle between the system and the preset aging effect axis and stress effect axis, the system determines that the main contribution to this performance degradation comes from electrochemical aging, and its health state evolution conforms to the expected life model.

[0045] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A high protection potted button supercapacitor, characterized in that, include: A supercapacitor cell that has been potted and encapsulated; A non-volatile memory integrated with a supercapacitor cell; The non-volatile memory stores a set of calibration data and a thermal transient response fingerprint; During the entire thermodynamic process of potting, curing and cooling of the supercapacitor cell, the equivalent series resistance of the supercapacitor cell is monitored in situ to obtain performance evolution data. Based on the performance evolution data, calibration data characterizing the individualized functional relationship between the equivalent series resistance and temperature of the supercapacitor cell after the potting process is generated. Thermal transient response fingerprints are characteristic parameters used to characterize the integrity of the encapsulation interface between a supercapacitor cell and its potting package. These parameters are obtained by monitoring the thermal relaxation process of the equivalent series resistance after applying a predicted energy electrical pulse to the supercapacitor cell, using calibration data as a temperature reference. The acquisition of thermal transient response fingerprints follows these internal rules: a functional relationship defined by the calibration data. inverse function The equivalent series resistance monitored during thermal relaxation The sequence is converted into an internal temperature. The decay sequence is obtained, and the thermal transient response fingerprint is extracted based on the decay sequence of the internal temperature, where, This refers to the time after the thermal excitation ends. Furthermore, the calibration data is stored in non-volatile memory in the form of a set of polynomial coefficients describing individualized functional relationships, or a lookup table for indexing individualized functional relationships. The thermal transient response fingerprint is a characteristic time constant of the decay of the equivalent series resistance during thermal relaxation.

2. A high protection potted button supercapacitor according to claim 1, characterized in that, The thermal transient response fingerprint is further defined as a differential index, which is obtained by comparing the characteristic time constant of the supercapacitor cell after it is encapsulated with the initial characteristic time constant of the supercapacitor cell before it is encapsulated. This differential index is used to offset the influence of environmental factors on the integrity of the encapsulation interface.

3. The high-protection potted button-type supercapacitor according to claim 1, characterized in that, The calibration data stored in the non-volatile memory is also used to characterize a second integral function relationship between the reactance and temperature of the supercapacitor cell; the equivalent series resistance and reactance together constitute a two-dimensional initial state space, which is configured to distinguish whether the performance degradation of the supercapacitor is due to the physical stress effect of initial curing or the effect of subsequent electrochemical aging during its service life.

4. The high ruggedization potted button supercapacitor of claim 1, wherein, The calibration data and thermal transient response fingerprint stored in the non-volatile memory are both obtained by performing matched filtering on the original monitoring signal. The matched filtering is performed based on the expected signal shape that the original monitoring signal should theoretically have.

5. A high-protection potted button-type supercapacitor according to claim 1, characterized in that, The non-volatile memory also stores a quality control flag, which is used to indicate the acquisition of calibration data and thermal transient response fingerprints. This flag is executed only after the electrical contact integrity between the pre-diagnostic confirmation test system and the supercapacitor cell meets the preset conditions. The pre-diagnostic test is based on the spectrum analysis of the baseline electrical noise signal of the supercapacitor cell in steady state and the determination of whether the energy of its low-frequency noise components is lower than the preset threshold.

6. A high-protection potted button-type supercapacitor according to claim 2, characterized in that, The thermal transient response fingerprint is a feature vector extracted by morphological analysis of the complete decay curve of the equivalent series resistance during thermal relaxation. The morphological analysis includes multi-exponential function fitting or multi-moment analysis of the complete decay curve to obtain multiple morphological feature parameters for identifying defect patterns at the package interface. The feature vector is configured to be matched with a preset defect fingerprint library to output a categorizable defect pattern diagnosis result.

7. A method for preparing a high-protection potted button-type supercapacitor, used to operate the high-protection potted button-type supercapacitor according to claim 1, characterized in that, Includes the following steps: Step a: During the entire thermodynamic process of potting, curing and cooling a supercapacitor cell, the equivalent series resistance of the supercapacitor cell is monitored in situ to obtain performance evolution data, and based on the performance evolution data, calibration data characterizing the individualized functional relationship between the equivalent series resistance and temperature of the supercapacitor cell after the potting process is generated. Step b: After generating calibration data, an electric pulse of known energy is applied to the supercapacitor cell to generate thermal excitation, and the calibration data generated in step a is used as a temperature reference to monitor the thermal relaxation process of the equivalent series resistance of the supercapacitor cell, and a thermal transient response fingerprint is extracted to characterize the integrity of the encapsulation interface between the supercapacitor cell and the potting package. Step c: Store the calibration data and thermal transient response fingerprint in a non-volatile memory integrated with the supercapacitor cell.

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