A non-destructive testing method, system, equipment, and medium for testing the degree of polymerization and uniformity of solid electrolytes.

Abstract

This invention discloses a non-destructive testing method for the polymerization degree and uniformity of solid electrolytes, comprising: connecting the in-situ polymerized solid battery to be tested into a testing system; applying an alternating electric field to the inside of the battery through the tabs of the solid battery; emitting ultrasonic pulses into the solid battery and receiving the original ultrasonic echo signal penetrating the solid battery; demodulating the original ultrasonic echo signal based on the frequency of the alternating electric field using the phase-locked differential principle to extract dynamic perturbation components; and reconstructing and outputting a three-dimensional map of the polymerization degree and uniformity of the solid electrolyte based on the dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model. This method overcomes the data acquisition obstacle caused by the high-gain circuit easily leading to signal saturation and truncation under severe Joule thermal drift conditions, ensuring that the system can achieve high-confidence non-destructive extraction of nanosecond-level microscopic forced vibration characteristics in a complex thermoacoustic coupling environment with extremely low signal-to-noise ratio.

Description

Technical Field

[0001] This invention relates to a method for testing the degree of polymerization and uniformity of solid electrolytes, and more particularly to a non-destructive testing method for testing the degree of polymerization and uniformity of solid electrolytes. Background Technology

[0002] In the field of solid-state battery technology, in-situ polymerization is considered one of the key pathways to achieve high-performance electrolyte preparation. However, the core technical challenge of this process lies in how to accurately assess the uniformity and integrity of the internal polymerization reaction after battery encapsulation. Existing non-destructive testing technologies are mainly developing along two routes: electrochemical detection and static physical transmission imaging.

[0003] Electrochemical detection methods can reflect the overall ionic conductivity characteristics of a battery at a macroscopic level, providing a useful reference for assessing the average polymerization state of the electrolyte. However, they essentially obtain a global equivalent parameter, which cannot achieve precise spatial localization of defects within the battery and lacks the ability to distinguish the non-uniformity of polymerization distribution and the spatial location information of local unreacted areas. On the other hand, static physical transmission imaging techniques, represented by conventional ultrasonic scanning, while possessing good three-dimensional spatial detection capabilities and able to penetrate the battery casing to obtain acoustic images of the internal structure, rely heavily on the acoustic impedance changes caused by differences in the static density of the medium.

[0004] In practical testing scenarios, two types of defects with vastly different properties may coexist within solid electrolytes: physical pore defects and chemically unpolymerized liquid monomer residues. Studies have found that these two types often exhibit highly similar attenuation characteristics in their static acoustic impedance properties. That is, both physical voids and liquid residues show similar low impedance and high attenuation signal responses. This makes it impossible for traditional ultrasonic detection techniques to distinguish the specific type of defect from its chemical nature—whether it is a structural pore or an unpolymerized liquid monomer residue.

[0005] Therefore, it is evident that overcoming the technical contradiction between macroscopic spatial positioning capability and microscopic chemical state discrimination capability in a fully enclosed and non-removable battery casing, and achieving accurate identification of unpolymerized liquid monomers and physical voids, thereby completing the spatial quantitative characterization of the degree of polymerization distribution, has become a long-standing and difficult-to-overcome technical challenge in the existing technology. Summary of the Invention

[0006] This invention overcomes the shortcomings of the prior art and provides a non-destructive testing method for the degree of polymerization and uniformity of solid electrolytes.

[0007] To achieve the above objectives, the technical solution adopted by this invention is: a non-destructive testing method for the degree of polymerization and uniformity of solid electrolytes, comprising the following steps:

[0008] S1: Connect the in-situ polymer solid-state battery to be tested to the test system and apply an alternating electric field to the inside of the battery through the tabs of the solid-state battery;

[0009] S2: While applying an alternating electric field, ultrasonic pulses are emitted into the solid-state battery, and the original ultrasonic echo signal that penetrates the solid-state battery is received.

[0010] S3: Using the phase-locked differential principle, based on the frequency of the alternating electric field, the original ultrasonic echo signal is demodulated to extract the dynamic perturbation component;

[0011] S4: Based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of solid electrolyte is reconstructed and output.

[0012] In a preferred embodiment of the present invention, in S1, an alternating electric field is applied to the interior of the battery through the tabs of the solid-state battery, including:

[0013] A weak alternating electric field with constant amplitude and dynamic frequency sweep is applied to a solid-state battery;

[0014] The frequency range of the weak alternating electric field sweep is controlled to cover the intrinsic dielectric relaxation characteristic frequencies of the polar chain segments in the solid electrolyte formulation under test.

[0015] In a preferred embodiment of the present invention, in step S2, an ultrasonic pulse is emitted into the solid-state battery, and the original ultrasonic echo signal penetrating the solid-state battery is received, including:

[0016] The casing of a solid-state battery is scanned in two or three dimensions using an array of ultrasonic transmitters and receivers.

[0017] The original ultrasonic echo signals under different spatial coordinates are acquired simultaneously. The original ultrasonic echo signals contain ultrasonic flight time and acoustic amplitude attenuation information.

[0018] In a preferred embodiment of the present invention, in S3, the original ultrasonic echo signal is demodulated based on the frequency of the alternating electric field using the phase-locked differential principle to extract dynamic perturbation components, including:

[0019] The frequency of the alternating electric field is used as a reference signal input to the lock-in amplifier;

[0020] The frequency-beat differential perturbation component that is at the same frequency as the reference signal or has a preset beat frequency relationship is extracted from the original ultrasonic echo signal by using a lock-in amplifier for mixing and noise reduction.

[0021] By utilizing frequency-based differential perturbation components, temperature drift caused by Joule heating inside the battery and background noise caused by static structures are filtered out.

[0022] In a preferred embodiment of the present invention, in S4, based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of the solid electrolyte is reconstructed and output, including:

[0023] Extract the amplitude of the acoustic resonance absorption peak of the dynamic perturbation component during the frequency sweep process of the alternating electric field;

[0024] The amplitude of the acoustic resonance absorption peak is substituted into the pre-established dynamic acoustoelastic modulus response and matched with the crosslinking density correlation database to calculate the actual degree of polymerization value at the corresponding spatial coordinate point.

[0025] Based on the actual aggregation degree values ​​of each spatial coordinate point, a three-dimensional heat map showing the aggregation degree distribution is generated.

[0026] In a preferred embodiment of the present invention, in S4, the dynamic perturbation component is used to characterize the degree of dipole polarization reversal of the material inside the solid-state battery under an alternating electric field, so as to distinguish physical pores from unpolymerized liquid monomers in a three-dimensional map.

[0027] Among them, the dynamic perturbation component corresponding to physical pores approaches zero, while the dynamic perturbation component corresponding to unpolymerized liquid monomers is excited to a value higher than the set threshold.

[0028] In a preferred embodiment of the present invention, the in-situ polymerized solid-state battery to be tested is a finished solid-state battery that is packaged with an aluminum-plastic film soft-pack shell or a metal shell and has completed the in-situ heating polymerization process inside.

[0029] A non-destructive testing system for the degree of polymerization and uniformity of solid electrolytes, the system being used to perform non-destructive testing methods for the degree of polymerization and uniformity of solid electrolytes, comprising:

[0030] The excitation module is used to connect the in-situ polymer solid-state battery under test to the test system and apply an alternating electric field with set parameters to the inside of the battery through the tabs of the solid-state battery.

[0031] The transceiver module is used to transmit ultrasonic pulses into the solid-state battery and receive the original ultrasonic echo signals that penetrate the solid-state battery while applying an alternating electric field.

[0032] The demodulation module is used to demodulate the original ultrasonic echo signal based on the frequency of the alternating electric field using the phase-locked differential principle, and to extract the dynamic perturbation component.

[0033] The reconstruction module is used to reconstruct and output a three-dimensional spectrum of the polymerization degree and uniformity of solid electrolytes based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model.

[0034] An electronic device, characterized in that it comprises:

[0035] At least one processor; and

[0036] A memory that is communicatively connected to at least one processor; wherein,

[0037] The memory stores a computer program that can be executed by at least one processor, which enables the at least one processor to perform a test method for non-destructive testing of the degree of polymerization and uniformity of solid electrolytes.

[0038] A computer-readable storage medium storing computer instructions for causing a processor to execute a test method for non-destructive testing of the polymerization degree and uniformity of a solid electrolyte.

[0039] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0040] (1) This invention provides a non-destructive testing method, system, equipment, and medium for testing the polymerization degree and uniformity of solid electrolytes. During ultrasonic spatial scanning, a dynamic frequency-sweeping alternating electric field covering the intrinsic dielectric relaxation characteristic frequency of polar chain segments is simultaneously applied to the interior of the solid battery through the tabs. The alternating electric field forces the uncrosslinked high-degree-of-freedom polar molecules to undergo dipole polarization reversal, thereby exciting the acoustoelastic modulus response inside the battery. This process introduces a dynamic forced vibration change modulated by the alternating electric field frequency in the macroscopic acoustic transmission link, establishing a direct ultrasonic field strength variable. Compared to traditional non-destructive testing techniques that rely primarily on the physical differences in the static density of the medium for imaging, which prevents the chemical differentiation between physically porous defects with extremely similar attenuation characteristics and unpolymerized liquid monomer residues, this invention breaks through the physical barrier of static detection in a single acoustic field. By capturing the physical transformation of the aforementioned microscopic polarization response spatial location into macroscopic acoustic parameter characteristics, this invention successfully achieves high sensitivity and accurate qualitative identification of unpolymerized liquid monomers and physical voids even when the battery casing is completely sealed.

[0041] (2) This invention provides a non-destructive testing method, system, equipment, and medium for testing the polymerization degree and uniformity of solid electrolytes. It employs a phase-locked differential principle to demodulate the acquired raw ultrasonic echo signal, directly using the frequency of the applied alternating electric field as a reference. A dual-channel orthogonal coherent demodulation model performs mixing, noise reduction, and integration on the broadband time-domain raw echo. Utilizing the bandpass coherent integral filtering characteristics of the orthogonal trigonometric function set, it intercepts and amplifies dynamic perturbation components with strictly synchronous frequency characteristics with the reference signal in the signal processing channel. Simultaneously, under the effect of integration delay, it causes the non-synchronous low-frequency drift and the DC constant term to tend towards the same frequency. Compared to conventional electronic bandpass filters, which are prone to thermal elastic noise leakage in adjacent frequency bands due to passband edge roll-off attenuation, thus drowning out weak polarization responses, this invention can completely filter out the slow temperature baseline drift caused by the continuous heat generated inside the battery by alternating current, as well as DC reflection noise caused by static structures such as battery packaging components and electrode stacking. This demodulation mechanism fundamentally overcomes the data acquisition obstacle that high-gain circuits are prone to signal saturation and truncation under severe Joule thermal drift conditions, ensuring that the system can achieve high-confidence, lossless extraction of nanosecond-level micro-forced vibration characteristics in complex thermo-acoustic coupling environments with extremely low signal-to-noise ratios.

[0042] (3) This invention provides a non-destructive testing method, system, equipment and medium for testing the degree of polymerization and uniformity of solid electrolytes. In the data fusion processing stage, the system extracts the maximum amplitude of the acoustic resonance absorption peak of the perturbation component in the full sweep frequency cycle, and uses it as an index to substitute into the preset physical modulus empirical equation with a natural exponential decay law. The parameter characterizing the macroscopic sound wave energy dissipation is directly converted into quantitative data of the actual crosslinking density at the microscopic level, and a three-dimensional thermogram reflecting the spatial gradual change state of the degree of polymerization is rendered and output. Compared with the existing detection technology that relies on a single acoustic attenuation parameter to make linear proportional calculations, the technical defects of the polarity response signal truncation leading to data overflow and serious distortion of the degree of polymerization determination are easy to occur in the extreme region of the degree of polymerization. This invention accurately depicts the real physical dissipation process in which the difficulty of polarization reversal of the polymer network chain segments increases sharply with the increase of crosslinking density. The spectrum reconstruction mechanism accurately restores the abstract discrete electroacoustic coupling calculation results to the three-dimensional physical space nodes of the solid battery, providing an intuitive, anti-interference and highly fidelity spatial quantitative characterization means for the uniformity testing of in-situ polymerized solid electrolytes. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart of a preferred embodiment of the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0047] Application Overview:

[0048] The core technical challenge of in-situ polymerization in solid-state batteries lies in accurately assessing the uniformity and integrity of the internal reaction after battery encapsulation. Existing non-destructive testing technologies are mainly divided into two routes: electrochemical detection and static physical transmission imaging. The electrochemical detection route can reflect the macroscopic ionic conductivity characteristics of the battery, but it only obtains global equivalent parameters and cannot achieve precise spatial positioning of internal local defects. On the other hand, the static physical transmission imaging route, such as conventional ultrasonic scanning, has good three-dimensional spatial detection capabilities, but its mechanism mainly relies on the physical differences in the static density of the medium for imaging.

[0049] For physical pore defects and unpolymerized liquid monomer residues inside solid electrolytes, both exhibit highly similar attenuation characteristics in static acoustic impedance. This makes it impossible for traditional detection techniques to distinguish the specific types of defects from a chemical perspective. How to overcome the technical contradiction between macroscopic spatial positioning capability and microscopic chemical state resolution capability in a fully enclosed battery casing, and achieve accurate identification of unpolymerized liquid monomers and physical voids as well as spatial quantitative characterization of polymerization degree distribution, is a difficult technical problem to solve in the existing technology.

[0050] For applications where the internal polymerization state of fully enclosed solid-state batteries is difficult to detect accurately and non-destructively, this invention addresses the challenges of qualitatively assessing internal chemical defects and quantitatively evaluating the degree of polymerization by introducing a characteristic frequency alternating electric field perturbation in conjunction with phase-locked differential modulation. During ultrasonic spatial scanning, an alternating electric field covering the polar segments of the target material and its intrinsic dielectric relaxation characteristic frequency is simultaneously applied. Utilizing the significant difference in dipole polarization reversal between unpolymerized liquid monomers and deeply cross-linked solid polymers under electric field induction, a dynamic acoustoelastic modulus response is excited. Furthermore, the dynamically modulated perturbation component is extracted through a phase-locked differential mechanism, thereby filtering out temperature drift caused by Joule heating within the battery and background noise caused by static structures.

[0051] Compared to existing technologies that rely on static physical differences in the medium for imaging, this invention breaks through the limitations of single acoustic field detection. By establishing a cross-physical field mapping relationship between the dielectric response of the alternating electric field and the macroscopic acoustic echo, it not only effectively distinguishes physical pores from unpolymerized liquid monomers by the presence or absence of dynamic perturbation components, but also inverts the actual crosslinking density by matching the amplitude of the resonance absorption peak, ultimately reconstructing a high-precision three-dimensional thermodynamic spectrum of the degree of polymerization. This provides a testing method with strong anti-interference ability and high chemical sensitivity for the homogeneity testing of in-situ polymerized solid electrolytes.

[0052] Example 1:

[0053] A non-destructive testing method for determining the degree of polymerization and uniformity of solid electrolytes includes the following steps:

[0054] S1: Connect the in-situ polymer solid-state battery to be tested to the test system and apply an alternating electric field to the inside of the battery through the tabs of the solid-state battery;

[0055] S2: While applying an alternating electric field, ultrasonic pulses are emitted into the solid-state battery, and the original ultrasonic echo signal that penetrates the solid-state battery is received.

[0056] S3: Using the phase-locked differential principle, based on the frequency of the alternating electric field, the original ultrasonic echo signal is demodulated to extract the dynamic perturbation component;

[0057] S4: Based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of solid electrolyte is reconstructed and output.

[0058] It should be noted that this invention constructs a cross-physical field collaborative detection mechanism combining alternating electric field perturbation and ultrasonic detection. During ultrasonic spatial scanning, an alternating electric field is simultaneously applied to the interior of the solid-state battery through the tabs. The alternating electric field induces uncrosslinked polar molecules to generate dipole polarization reversal. Then, using the phase-locked differential principle, based on the frequency of the alternating electric field itself, the ultrasonic echo signal is demodulated to extract the perturbation component reflecting the dynamic response of the material. Based on this data, a three-dimensional polymerization degree map is reconstructed, achieving the technical effect of accurately distinguishing defect types and outputting the spatial polymerization degree distribution. This enables non-destructive qualitative identification of internal chemical defects in in-situ polymerized solid-state batteries and quantitative assessment of the spatial distribution of polymerization degree. It solves the technical problem that existing physical transmission detection technology cannot distinguish physical pores from unpolymerized liquid monomer residues from a chemical perspective, and it is difficult to accurately characterize the spatial differences in microscopic crosslinking density.

[0059] In the process of transforming this cross-physical field coupling detection concept into a stable and reliable feasible solution, it is necessary to solve the problem of multi-source signal crosstalk generated after the introduction of alternating electric fields. The key is to overcome the acoustic baseline drift barrier caused by the electrothermal effect. When an alternating electric field is applied to the inside of the battery to induce polar chain segment response, the current passing through the internal components of the battery will inevitably generate Joule heating. Small fluctuations in the temperature of the medium will cause thermal expansion of the material and drastic changes in the propagation speed of ultrasonic waves. This thermoacoustic background noise, which is composed of global temperature drift and battery static structure, will completely drown out the weak dynamic sonic boom signal excited by the local polarization reversal of unpolymerized monomers, making it impossible for the ultrasonic receiver to extract the true and effective data reflecting the degree of polymerization.

[0060] To overcome the aforementioned thermo-acoustic coupling interference and static background noise barriers, this invention constructs a closed-loop detection framework based on synchronous excitation and same-frequency reference noise reduction. After the in-situ polymer solid-state battery under test is connected to the test system, an alternating electric field of a specific frequency is applied to the inside of the battery through the tabs of the solid-state battery to excite the dynamic dielectric response of the internal material. During the application of the electric field, the detection device emits ultrasonic pulses into the solid-state battery and simultaneously receives the original ultrasonic echo signal that penetrates the battery.

[0061] The system uses the frequency of the applied alternating electric field as a reference input and performs frequency mixing and demodulation on the original ultrasonic echo signal using the phase-locked differential principle. It removes the static background data affected by temperature drift and extracts the dynamic perturbation component that is only modulated by the electric field. The system finally extracts the characteristic value of the dynamic perturbation component, combines it with the synchronously recorded spatial coordinate scanning data and the preset correlation model for matching calculation, and then reconstructs and outputs a three-dimensional map of the polymerization degree and uniformity of the solid electrolyte.

[0062] Example 2:

[0063] S1: Connect the in-situ polymer solid-state battery to be tested to the test system and apply an alternating electric field to the inside of the battery through the tabs of the solid-state battery;

[0064] In a preferred embodiment of the present invention, in S1, an alternating electric field is applied to the interior of the battery through the tabs of the solid-state battery, including:

[0065] A weak alternating electric field with constant amplitude and dynamic frequency sweep is applied to a solid-state battery;

[0066] The frequency range of the weak alternating electric field sweep is controlled to cover the intrinsic dielectric relaxation characteristic frequencies of the polar chain segments in the solid electrolyte formulation under test.

[0067] It should be noted that connecting the in-situ polymer solid-state battery under test to the test system and applying an alternating electric field to the inside through the tabs is the primary basic operation for establishing a cross-physical field mapping detection mechanism. In the specific execution process, the operation terminal connects the output of the broadband AC signal generator to the positive and negative tabs of the solid-state battery through a wire loop, so that the solid electrolyte inside the battery is placed in the established dynamic electric field environment.

[0068] The above steps constitute the active disturbance source of the entire non-destructive testing system. Addressing the technical problem that static physical acoustic impedance testing cannot distinguish the internal physical pores and the essential differences between them and unpolymerized liquid monomers, an active electric field is applied to force polar molecules in the solid electrolyte to undergo forced motion. This step effectively changes the micromechanical state of the medium inside the uncrosslinked region, providing the necessary modulation input prerequisite for subsequent capture of structural dynamic changes by ultrasonic pulses and extraction of co-frequency perturbation signals using a lock-in amplification mechanism.

[0069] When performing the above-mentioned tab connection and electric field application operations, the device control unit applies a weak alternating electric field with constant amplitude and dynamic frequency sweep to the solid-state battery. The amplitude parameter of the weak alternating electric field is set in the low potential range to ensure that the voltage difference applied to the two electrodes of the battery is limited within the electrochemical stability window of the solid electrolyte system, so as to avoid abnormal migration of lithium ions caused by high voltage environment or triggering irreversible redox side reactions at the electrode interface.

[0070] The alternating electric field is controlled to exhibit dynamic frequency sweeping changes, and the frequency sweeping range is limited to cover the intrinsic dielectric relaxation characteristic frequencies of polar segments in the test formulation. This is because polymers with different crosslinking densities exhibit different degrees of restriction on the movement of microscopic segments. Unpolymerized liquid monomers have large free volumes and fast polar group reversal rates, and their response frequencies are usually in the higher frequency bands. However, the three-dimensional network of deeply crosslinked and cured polymers imposes strong steric hindrance on polar segments, resulting in slow polarization response or even failure to respond. The system uses dynamic frequency sweeping to traverse the set frequency bands to find and locate the specific excitation frequency point that maximizes the polarization reversal amplitude in the unpolymerized monomer region.

[0071] In this step, a frequency-sweeping excitation determination mechanism is constructed by introducing a dissipation optimization model. This mechanism utilizes the resonance matching effect between the applied alternating electric field frequency and the relaxation time of the dipole moment flip of the target defect polar molecule to quantify the energy dissipation law caused by dielectric polarization in different polymerization state spaces. The specific calculation model uses the imaginary part of the complex permittivity. The formula for characterizing the strength of polarization dissipation within a medium is set as follows: In this formula calculation, the parameters The low-frequency static dielectric constant of the solid electrolyte formulation to be tested is given by the parameter. The dielectric constant of high-frequency optical signals, parameter The parameter represents the real-time angular frequency of the currently applied alternating electric field. The characteristic relaxation time represents the local polarity of the chain segment in space.

[0072] The system continuously updates parameters during the frequency sweep process. The value is due to the characteristic relaxation time of the unpolymerized monomer region. It belongs to the constant term, and according to this calculation model, it is determined if and only if the angular frequency is... With characteristic relaxation time When the condition that the product of the two equals one is met, the imaginary part of the complex permittivity reaches its maximum value. The system captures the sweep frequency point corresponding to this extreme value and locks the output. The introduction of this dissipative optimization model solves the problems of low excitation efficiency and weak signal caused by blindly applying a single fixed frequency. This improvement enables the system to achieve nonlinear amplification of the local unpolymerized monomer perturbation signal under the constraint of a safe and weak electric field by utilizing the characteristic frequency resonance effect. This effectively overcomes the engineering obstacle that traditional detection must rely on increasing the driving voltage to increase the response amplitude, thereby damaging the electrochemical structure of the battery.

[0073] S2: While applying an alternating electric field, ultrasonic pulses are emitted into the solid-state battery, and the original ultrasonic echo signal that penetrates the solid-state battery is received.

[0074] In a preferred embodiment of the present invention, in step S2, an ultrasonic pulse is emitted into the solid-state battery, and the original ultrasonic echo signal penetrating the solid-state battery is received, including:

[0075] The casing of a solid-state battery is scanned in two or three dimensions using an array of ultrasonic transmitters and receivers.

[0076] The original ultrasonic echo signals under different spatial coordinates are acquired simultaneously. The original ultrasonic echo signals contain ultrasonic flight time and acoustic amplitude attenuation information.

[0077] It should be noted that while applying a dynamic electric field excitation to the solid-state battery, the system controls an external detection device to emit ultrasonic pulses into the solid-state battery and continuously receives the original ultrasonic echo signal penetrating the battery. The system instructs the ultrasonic probe assembly to be in close contact with the encapsulation material on the outside of the solid-state battery. Through a piezoelectric chip, the high-frequency electrical pulse is converted into a high-frequency mechanical vibration wave, which is then coupled and transmitted into the layered structure of the battery. When the acoustic energy penetrates the electrode sheet and the solid electrolyte region, transmission and reflection inevitably occur. The receiving chip placed on the opposite or same side of the array captures the echo signal carrying the propagation trajectory characteristics inside the medium in real time. This constitutes a signal acquisition channel that combines spatial acoustic scanning with time dimension tracking. To address the technical problem that electrochemical testing alone cannot obtain the local anomaly location information of the internal space, this step establishes an acoustic carrier transmission link modulated by the electric field. This receives the changes in the microscopic mechanical forced vibration excited by the alternating electric field applied in the front-end step and provides it as a physical signal output medium for subsequent steps to perform phase-locked frequency beat feature demodulation. This realizes the physical transformation of the spatial position of the microscopic chemical response into the macroscopic acoustic parameter characteristics.

[0078] To acquire detailed spatial detection information across the entire system, the system drives an ultrasonic transmitter and receiver array mounted on a moving slide to perform a gridded two-dimensional or tomographic three-dimensional scanning motion on the surface of the solid-state battery casing. When the scanning mechanism reaches each preset grid coordinate point, the signal acquisition device simultaneously records the original ultrasonic echo signal at the corresponding spatial coordinates. The acquired original ultrasonic echo signal is quantized in the time and amplitude dimensions. The data stream contains ultrasonic time-of-flight parameters characterizing the speed and total distance traveled by the sound wave in the medium, as well as acoustic amplitude attenuation information characterizing the total absorption and scattering loss of the sound wave within the medium. Through the binding operation of the spatial coordinate system and acoustic echo characteristic parameters, the system establishes a multi-dimensional discrete detection dataset, ensuring global data coverage without detection blind spots for solid-state battery entities with large-area winding or stacked packaging configurations.

[0079] This embodiment employs a dynamic acoustic-elastic coupling nonlinear mapping model to construct a time-domain sound velocity and attenuation feature extraction mechanism. It quantifies the nonlinear acoustic parameter changes induced by the electric field-polarized stress field modulation during ultrasonic propagation. The specific calculation model uses the dynamic sound wave transmission vector modulus... Characterizing the comprehensive disturbance features during sound wave propagation, the model calculation formula is defined as follows: .

[0080] In the calculation system of the above formula, the parameters The initial angular frequency of the ultrasonic waves emitted by the probe array, parameters The parameter represents the static baseline sound velocity of the solid electrolyte at this ambient temperature. The electric field intensity variable that varies with time within the current spatial coordinate point.

[0081] Model introduces parameters The sound velocity polarization sensitivity coefficient, as a medium, is introduced to characterize the intensity of the sound wave time-of-flight shift caused by the electric field. As a nonlinear acoustic attenuation dissipation coefficient, it characterizes the degree of attenuation of sound amplitude induced by the electric field, and is expressed in imaginary units. Separate the velocity parameter and the decay parameter in complex space.

[0082] After acquiring the raw echoes at each coordinate point, the system applies the model to perform characteristic wave vector fitting. This mapping model solves the technical defect of traditional static acoustic detection, which cannot extract dynamic mechanical response components, leading to parametric aliasing. This improvement establishes a mathematical connection between the electric field intensity variable and the time of flight, and the amplitude parameter fluctuation. It overcomes the algorithmic obstacle that simple time-domain signals cannot analyze the electrically induced forced vibration components, ensuring that the massive amount of raw acoustic data captured during array scanning has a standardized and unified premise that can be accurately processed by subsequent differential demodulation algorithms.

[0083] S3: Using the phase-locked differential principle, based on the frequency of the alternating electric field, the original ultrasonic echo signal is demodulated to extract the dynamic perturbation component;

[0084] In a preferred embodiment of the present invention, in S3, the original ultrasonic echo signal is demodulated based on the frequency of the alternating electric field using the phase-locked differential principle to extract dynamic perturbation components, including:

[0085] The frequency of the alternating electric field is used as a reference signal input to the lock-in amplifier;

[0086] The frequency-beat differential perturbation component that is at the same frequency as the reference signal or has a preset beat frequency relationship is extracted from the original ultrasonic echo signal by using a lock-in amplifier for mixing and noise reduction.

[0087] By utilizing frequency-based differential perturbation components, temperature drift caused by Joule heating inside the battery and background noise caused by static structures are filtered out.

[0088] It should be noted that the system extracts the frequency data of the alternating electric field applied at the front end and sets it as a reference. Using the phase-locked differential principle, it performs demodulation operations on the synchronously received raw ultrasonic echo signal, thereby extracting the dynamic perturbation components hidden in the complex background signal. In the specific signal flow operation, the hardware circuit or digital signal processor intercepts the broadband time-domain raw echo containing a large amount of environmental interference and transmits it synchronously to the phase-locked amplification channel. It performs a coherent comparison operation with the extracted pure reference frequency signal. To address the technical problem that the application of the electric field will inevitably cause the battery's internal current to do work, resulting in slight temperature fluctuations, which will seriously change the basic acoustic propagation parameters, this step blocks the transmission path of non-co-frequency noise by establishing a strict frequency domain locking and differential screening mechanism.

[0089] In the overall system operation process described above, the slow thermoelastic background noise mixed in the ultrasonic signal and the reflection information of the static solidified physical structure are completely stripped away, providing a highly purified and reliable source of data that only reflects the forced motion state of the polar chain segments of the polymer for the subsequent rendering and reconstruction of the spatial three-dimensional map.

[0090] When performing the above-mentioned phase-locked differential demodulation operation, the system intercepts the frequency parameters of the alternating electric field directly applied to the battery tab and converts them into a reference signal of standard potential format, which is then input to the phase-locked amplifier. Subsequently, the original ultrasonic echo signal entering the channel is mixed and denoised. Through the internal multiplier array and integrator circuit elements, all frequency components contained in the ultrasonic echo are screened, and only the frequency beat differential perturbation components that have strict same frequency characteristics with the reference signal or conform to the preset mathematical beat frequency relationship are retained and amplified.

[0091] The system further utilizes the output beat differential perturbation component to perform inverse noise filtering. Due to the Joule heating effect generated by the current flowing through the equivalent impedance inside the battery, it manifests as a slow-accumulating global temperature drift in macroscopic physics, which corresponds to a slow baseline shift at extremely low frequencies in sound wave transmission. The static structure of the battery packaging components, inherent physical pores, and electrode stacking has a constant DC response to ultrasonic waves. Neither of these two typical interference sources has the dynamic frequency shift characteristic of high-frequency reversal with the external alternating electric field in the frequency domain. The system, with its lock-in amplification mechanism, has an extremely high suppression ratio parameter for incoherent frequencies, blocking the low-frequency temperature drift background and DC static structural noise, and intercepting dynamic parameters characterizing the true degree of cross-linking of local cells.

[0092] In this step, an underlying algorithm mechanism for dynamic perturbation feature extraction is constructed by employing an orthogonal dual-channel coherent demodulation model. This model utilizes the bandpass coherent integral filtering characteristics of the orthogonal trigonometric function set to losslessly downconvert the extremely weak high-frequency target modulated signal to DC baseband. Furthermore, it relies on a specific width of integral time delay to strongly suppress out-of-band uncorrelated random noise and low-frequency thermal drift components. The specific model calculation formula is set as the perturbation component amplitude... The formulas for calculating in-phase components and quadrature components are defined as follows: ,as well as .

[0093] In the above calculation formula model architecture, parameters The parameters characterize the total input parameters of the raw time-domain ultrasound echo acquired by the ultrasound receiving probe, including the DC static reflection signal, low-frequency thermal noise signal, and useful co-frequency modulated signal. The real-time driving angular frequency of the alternating electric field applied to the front end, parameters This represents the low-pass filter integral time constant, which is set based on the system's analog-to-digital conversion sampling rate and the target signal-to-noise ratio tolerance requirements.

[0094] The above algorithm specifically processes the input signal by performing a real-time product operation with two reference local oscillator signals that are 90° out of phase, and then limiting the time window width to... The integral stage calculates the time average of the continuous product results; based on the orthogonality operation logic of trigonometric functions, this is only true if the original ultrasonic echo input signal contains a frequency strictly equal to... When the dynamic perturbation component is present, the mathematical integral result can output a non-zero effective value, while the other slowly varying low-frequency thermal offset interference and the DC static term tend to zero and are discarded by the system under sufficiently long time integration.

[0095] The above-mentioned orthogonal demodulation model solves the algorithmic defect of conventional electronic bandpass filters, which is caused by thermoelastic noise leakage in adjacent frequency bands due to passband edge roll-off attenuation, thus submerging the weak mechanical polarization response. This improvement utilizes the strong nonlinear frequency selection characteristics of frequency domain coherent multiplication to achieve ultra-narrowband signal transmission. It overcomes the data acquisition obstacle of high-gain circuit amplification under severe Joule thermal drift conditions, which is prone to baseline saturation. This ensures that the system can stably extract nanosecond-level sound velocity phase perturbation parameters in harsh detection environments with extremely low signal-to-noise ratios.

[0096] S4: Based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of solid electrolyte is reconstructed and output.

[0097] In a preferred embodiment of the present invention, in S4, based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of the solid electrolyte is reconstructed and output, including:

[0098] Extract the amplitude of the acoustic resonance absorption peak of the dynamic perturbation component during the frequency sweep process of the alternating electric field;

[0099] The amplitude of the acoustic resonance absorption peak is substituted into the pre-established dynamic acoustoelastic modulus response and matched with the crosslinking density correlation database to calculate the actual degree of polymerization value at the corresponding spatial coordinate point.

[0100] Based on the actual aggregation degree values ​​of each spatial coordinate point, a three-dimensional heat map showing the aggregation degree distribution is generated.

[0101] In a preferred embodiment of the present invention, in S4, the dynamic perturbation component is used to characterize the degree of dipole polarization reversal of the material inside the solid-state battery under an alternating electric field, so as to distinguish physical pores from unpolymerized liquid monomers in a three-dimensional map.

[0102] Among them, the dynamic perturbation component corresponding to physical pores approaches zero, while the dynamic perturbation component corresponding to unpolymerized liquid monomers is excited to a value higher than the set threshold.

[0103] In a preferred embodiment of the present invention, the in-situ polymerized solid-state battery to be tested is a finished solid-state battery that is packaged with an aluminum-plastic film soft-pack shell or a metal shell and has completed the in-situ heating polymerization process inside.

[0104] It should be noted that in this step, after successfully extracting the pure dynamic perturbation component modulated by the electric field, the system control computing terminal fuses the extraction results with the spatial coordinate positioning data synchronously fed back by the flaw detection and scanning mechanism, and then performs mapping calculations based on the built-in preset a priori physical quantity association model. Finally, it reconstructs, renders, and outputs a three-dimensional digital map that reflects the true degree of polymerization and uniformity of the solid electrolyte.

[0105] During the data fusion and map reconstruction steps described above, the one-dimensional time-series perturbation feature values ​​continuously output by the phase-locked amplification stage are forcibly resampled according to the actual movement trajectory of the ultrasonic probe, and matrix matching is performed with the spatial triaxial coordinate parameters within the three-dimensional spatial grid. This operation restores the electroacoustic coupling calculation results without positional attributes to the physical internal structural nodes of the solid-state battery. Addressing the technical obstacle that traditional methods can only provide vague attenuation shadows and cannot quantify the true cross-linking density of the medium, this operation step acts as the translation and transformation hub from micro-polarization data to macro-quality inspection conclusions. It integrates the multi-independent data chains accumulated from previous active electric field excitation and array acoustic capture, effectively achieving the final system goal of intuitively displaying the integrity of the micro-chemical reactions inside the tested solid-state battery.

[0106] When refining the calculation and execution process of spectrum reconstruction and qualitative and quantitative analysis, the data processing module searches for extreme values ​​in the dynamic perturbation component dataset containing frequency point scanning history, and extracts the maximum amplitude parameter of the acoustic resonance absorption peak captured by the system within the full-band frequency sweep period of the alternating electric field.

[0107] The material property empirical database preloaded in the memory is queried. This prior database has a nonlinear mapping table built with dynamic acoustoelastic modulus response as the independent variable and corresponding crosslinking density as the dependent variable.

[0108] The acoustic resonance absorption peak amplitude parameters obtained above are directly substituted into the database as indexes, and the actual absolute degree of polymerization of the solid electrolyte in the micro-region to which the specific spatial coordinate point belongs is calculated by spline interpolation.

[0109] The system controls the graphics rendering engine to traverse all spatial coordinate points within the battery structure and retrieve the corresponding calculated actual aggregation degree values. Using a pseudo-color scale, the numerical values ​​are mapped to different color gradients, thereby rendering a three-dimensional thermal perspective spectrum that can intuitively present the internal defect boundaries and the spatial gradient distribution of aggregation degree.

[0110] In the logic of image analysis, the magnitude of the dynamic perturbation component directly characterizes the intensity of the polarization reversal response of the polar dipoles in the local material inside the solid-state battery under the forced action of an external alternating electric field. This characteristic value is used by the system as a key identification factor in the three-dimensional image rendering to distinguish between physical pore defects and unpolymerized liquid monomers with extremely similar macroscopic mechanical characteristics. Since the physical pores contain only air or other inert gases and lack polymer chain segments with polar moments, they cannot undergo dipole reversal and the accompanying acoustic energy dissipation after the application of an alternating electric field. Based on this, the system strictly locks its corresponding dynamic perturbation component to a base background minimum region that approaches zero.

[0111] The residual region of incompletely polymerized and solidified liquid monomers contains a large number of highly mobile polar groups because the polymer chain segments have not yet been cross-linked into a network. Under the excitation of a specific electric field frequency, it will cause a sharp polarization oscillation dissipation. Based on this, the system sets a logic threshold and judges the points that are excited to generate dynamic micro-perturbation characteristic signals significantly higher than the set threshold as unpolymerized liquid monomers and highlights them in the spectrum as alarms. The test implementation object of this detection system is clearly set as finished solid-state batteries that are completely sealed and closed by aluminum-plastic composite film soft packaging or hard metal shell, and have completed the internal in-situ heating and solidification polymerization process in the manufacturing process.

[0112] In this step, a polymer free volume characteristic relaxation modulus inversion model is used to construct the underlying theoretical mapping relationship for quantitative calculation of the degree of polymerization. This model, through the physical law that the dynamic mechanical dissipation parameter is inversely proportional to the microscopic free volume of the polymer network, transforms the captured macroscopic acoustic maximum energy loss value into quantitative crosslinking density data characterizing the completeness of the microscopic crosslinking chemical reaction. The specific mapping model uses the actual crosslinking density of the solid electrolyte. A metric characterizing aggregation completeness is defined, and the calculation formula is set as follows: .

[0113] Within the aforementioned computational model framework, parameters This is the theoretical maximum limiting crosslinking density constant under the ideal fully reactive crosslinking state in this formulation system. This represents the increment in the attenuation amplitude of the strongest acoustic resonance absorption peak extracted when the system's electric field frequency is matched to the dipole resonance point. (Parameter) The parameter is the local effective free volume coefficient of the polymer after correction for ambient temperature. For a specific electrolyte material formulation, the dimensionless constant of modulus polarization coupling sensitivity is calibrated. During the calculation, the maximum amplitude of the spatial point feedback is extracted and solved by a natural exponential function in combination with fixed parameters.

[0114] By applying the aforementioned characteristic relaxation modulus inversion calculation model, the algorithmic defects of severely distorted polymerization degree determination caused by linear proportional estimation based on a single acoustic attenuation parameter are completely solved. This model utilizes the introduction of a free volume constraint effect parameter with a natural exponential decay law to characterize the real microscopic physical process in which the difficulty of polarization reversal of network chain segments inside the polymer increases sharply with the nonlinear increase of crosslinking density. It effectively overcomes the data overflow obstacle caused by the saturation truncation of polar response signals in the extreme regions at both ends of the polymerization degree of traditional linear lookup table algorithms. This ensures that the color gradient of the final rendered three-dimensional thermogram can realistically and faithfully reproduce the spatial evolution law of the complex microscopic chemical state inside the battery.

[0115] A non-destructive testing system for the degree of polymerization and uniformity of solid electrolytes, the system being used to perform non-destructive testing methods for the degree of polymerization and uniformity of solid electrolytes, comprising:

[0116] The excitation module is used to connect the in-situ polymer solid-state battery under test to the test system and apply an alternating electric field with set parameters to the inside of the battery through the tabs of the solid-state battery.

[0117] The transceiver module is used to transmit ultrasonic pulses into the solid-state battery and receive the original ultrasonic echo signals that penetrate the solid-state battery while applying an alternating electric field.

[0118] The demodulation module is used to demodulate the original ultrasonic echo signal based on the frequency of the alternating electric field using the phase-locked differential principle, and to extract the dynamic perturbation component.

[0119] The reconstruction module is used to reconstruct and output a three-dimensional spectrum of the polymerization degree and uniformity of solid electrolytes based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model.

[0120] An electronic device, characterized in that it comprises:

[0121] At least one processor; and

[0122] A memory that is communicatively connected to at least one processor; wherein,

[0123] The memory stores a computer program that can be executed by at least one processor, which enables the at least one processor to perform a test method for non-destructive testing of the degree of polymerization and uniformity of solid electrolytes.

[0124] A computer-readable storage medium storing computer instructions for causing a processor to execute a test method for non-destructive testing of the polymerization degree and uniformity of a solid electrolyte.

[0125] It should be noted that the hardware architecture of this test system is mainly composed of an excitation module, a transceiver module, a demodulation module, and a reconstruction module. The data bus interconnection of the hardware units ensures the timing synchronization of active electric field disturbance and acoustic high-frequency acquisition.

[0126] The excitation module, as the active perturbation output terminal of the test system, is responsible for introducing external controlled alternating electric signals into the solid-state battery. It is based on applying a broadband alternating electric field to overcome the rotational potential barrier of the dipoles inside the electrolyte material, forcing the polar chain segments with high degrees of freedom to undergo orientation reversal. The excitation module uses an arbitrary waveform generator unit combined with a weak AC constant current source to construct the hardware entity. For example, the Keysight 33600A series waveform generator with high frequency resolution output characteristics is used as the signal source. This module provides the system with a dynamic dielectric excitation environment with adjustable parameters, solving the problem of the lack of internal medium chemical response difference induction source in traditional static detection, and ensuring the stable injection of polarization modulation perturbation signals.

[0127] The transceiver module transforms the microscopic polarization response characteristics of the battery's internal medium into a hardware acquisition task of macroscopically measurable signals. This module relies on the forward and inverse piezoelectric conversion effect of piezoelectric ceramic materials. By applying a high-frequency voltage to the piezoelectric crystal to excite electrical stress and generate mechanical vibration waves, these waves are injected into the solid-state battery. Subsequently, the attenuated transmission residual waves after penetrating the multi-layer internal structure are collected. The main body of the transceiver module is assembled from an ultrasonic pulse generator and receiver and a high-frequency array piezoelectric probe, such as the Olympus 5073PR broadband ultrasonic transceiver card paired with a focusing composite piezoelectric crystal probe, and supplemented by a multi-axis servo slide to control the spatial displacement of the probe. The setup of this module enables the penetration scanning of the dense gridded acoustic field of the battery's enclosed internal spatial structure, overcoming the limitation of single-point detection lacking overall spatial distribution data. It provides a high-frequency acoustic carrier substrate carrying dynamic perturbation variables for subsequent processing units.

[0128] The demodulation module is the core signal processing hub of the system, which removes background noise and purifies polarization feature data. Based on the physical algorithm principle of dual-channel orthogonal coherent demodulation, this module uses hardware multiplier units and low-pass integral filter components to forcibly filter out tiny electroacoustic coupling fluctuation parameters that are in sync with the reference frequency of the excitation module. At the hardware selection level, the demodulation module is usually equipped with a high-performance digital lock-in amplifier with extremely high dynamic reserve, such as the UHFLI series ultra-high frequency digital lock-in amplifier from Zurich Instruments, to meet the requirements of megahertz-level ultrasonic carrier mixing. The introduction of this module completely solves the problems of severe baseline thermal expansion drift and DC reflection interference caused by the inherent packaging structure of the battery under the continuous heat generation of alternating current, and realizes high-confidence lossless extraction of extremely weak polarization response signals under harsh detection environments.

[0129] The reconstruction module is the system's terminal data fusion and visualization physical unit, used to perform three-dimensional spatial mapping operations from low-level scattered acoustic data to high-order quality inspection images. This module is based on nonlinear spatial interpolation and physical modulus feature calibration principles, reprojecting the dimensionality-reduced feature time series into a three-dimensional spatial coordinate system, and converting the perturbation amplitude into actual aggregation degree values ​​according to the built-in dielectric modulus empirical equation. The reconstruction module relies on an industrial-grade control host equipped with a graphics processing unit, and uses the internal parallel computing core to perform three-dimensional voxel spatial rendering. This module transforms abstract discrete acoustic-electric coupling data into a three-dimensional thermal perspective image that intuitively presents the internal liquid monomer residual dead corners and unevenly cross-linked solidified areas, directly outputting the final qualitative and grading results that meet the quality inspection requirements of industrial production lines.

[0130] To ensure the automatic and continuous execution of the complex logic control timing and signal operation model of the above detection method, this solution constructs an electronic device entity containing at least one central processing unit and a memory that establishes a bidirectional communication connection with it. This electronic device is a computing workstation integrating an industrial-grade motherboard architecture. The memory uses a non-volatile solid-state drive and a high-speed random access memory array to persistently store computer programs containing instructions for frequency scanning control, transceiver array triggering, coherent operation calibration, and graphics rendering, as well as cache the massive amount of raw echo data generated during the operation of the device.

[0131] The processor serves as the logic scheduling and execution center. It extracts and executes code segments from the memory via the motherboard bus according to the preset microinstruction timing. This drives the aforementioned physical functional hardware modules to operate in coordination. The configuration of the electronic device's physical architecture enables the theory of non-destructive testing across physical fields to be transformed into an automated closed-loop testing flow without manual intervention. This ensures the timing accuracy of solving the massive mathematical model and the execution of the underlying peripheral devices, as well as the stability of system operation.

[0132] Storage media encompass industrial storage devices such as high-capacity flash memory chips, magnetic media drive disks, or onboard read-only memory modules on system motherboards, which possess the characteristic of persistent retention of digital level information. These devices physically solidify computer instructions that are translated into low-level machine language sequences by the compiler through semiconductor floating gate charge capture or magnetic pole array reversal.

[0133] When the instruction sequence is read, interpreted, loaded, and executed by the processor of the external host electronic device, it can completely reproduce the entire process of extracting electroacoustic perturbation features and reconstructing dielectric aggregation degree spectrum. The physical design of the computer-readable storage medium ensures the lossless and standardized distribution of the non-destructive testing statistical algorithm among different batches of hardware testing platforms, prevents the core demodulation algorithm code from being lost due to structural damage in the event of abnormal power failure of the equipment, and provides underlying data persistence guarantee for the large-scale production and manufacturing of testing equipment and the maintenance and upgrade of the subsequent software life cycle.

[0134] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A non-destructive testing method for the degree of polymerization and uniformity of solid electrolytes, characterized in that, Includes the following steps: S1: Connect the in-situ polymer solid-state battery to be tested to the test system and apply an alternating electric field to the inside of the battery through the tabs of the solid-state battery; S2: While applying an alternating electric field, ultrasonic pulses are emitted into the solid-state battery, and the original ultrasonic echo signal that penetrates the solid-state battery is received. S3: Using the phase-locked differential principle, based on the frequency of the alternating electric field, the original ultrasonic echo signal is demodulated to extract the dynamic perturbation component; S4: Based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of solid electrolyte is reconstructed and output.

2. The method according to claim 1, characterized in that: In S1, an alternating electric field is applied to the interior of the solid-state battery through the tabs, including: A weak alternating electric field with constant amplitude and dynamic frequency sweep is applied to a solid-state battery; The frequency range of the weak alternating electric field sweep is controlled to cover the intrinsic dielectric relaxation characteristic frequencies of the polar chain segments in the solid electrolyte formulation under test.

3. The method according to claim 1, characterized in that: In S2, ultrasonic pulses are emitted into the solid-state battery, and the original ultrasonic echo signals that penetrate the solid-state battery are received, including: The casing of a solid-state battery is scanned in two or three dimensions using an array of ultrasonic transmitters and receivers. The original ultrasonic echo signals under different spatial coordinates are acquired simultaneously. The original ultrasonic echo signals contain ultrasonic flight time and acoustic amplitude attenuation information.

4. The method according to claim 1, characterized in that: In step S3, the original ultrasonic echo signal is demodulated based on the frequency of the alternating electric field using the phase-locked differential principle to extract dynamic perturbation components, including: The frequency of the alternating electric field is used as a reference signal input to the lock-in amplifier; The frequency-beat differential perturbation component that is at the same frequency as the reference signal or has a preset beat frequency relationship is extracted from the original ultrasonic echo signal by using a lock-in amplifier for mixing and noise reduction. By utilizing frequency-based differential perturbation components, temperature drift caused by Joule heating inside the battery and background noise caused by static structures are filtered out.

5. The method according to claim 1, characterized in that: In step S4, based on dynamic perturbation components, combined with spatial coordinate scanning data and a preset correlation model, a three-dimensional spectrum of the polymerization degree and uniformity of the solid electrolyte is reconstructed and output, including: Extract the amplitude of the acoustic resonance absorption peak of the dynamic perturbation component during the frequency sweep process of the alternating electric field; The amplitude of the acoustic resonance absorption peak is substituted into the pre-established dynamic acoustoelastic modulus response and matched with the crosslinking density correlation database to calculate the actual degree of polymerization value at the corresponding spatial coordinate point. Based on the actual aggregation degree values ​​of each spatial coordinate point, a three-dimensional heat map showing the aggregation degree distribution is generated.

6. The method according to claim 1, characterized in that, In S4, the dynamic perturbation component is used to characterize the degree of dipole polarization reversal of the material inside the solid-state battery under an alternating electric field, in order to distinguish physical pores from unpolymerized liquid monomers in a three-dimensional map. Among them, the dynamic perturbation component corresponding to physical pores approaches zero, while the dynamic perturbation component corresponding to unpolymerized liquid monomers is excited to a value higher than the set threshold.

7. The method according to claim 1, characterized in that, The in-situ polymerized solid-state battery to be tested is a finished solid-state battery that is packaged with an aluminum-plastic film soft-pack shell or a metal shell and has completed the in-situ heating polymerization process inside.

8. A non-destructive testing system for the degree of polymerization and uniformity of solid electrolytes, characterized in that, The system is used to perform the non-destructive testing method for determining the degree of polymerization and uniformity of solid electrolytes according to any one of claims 1-7, comprising: The excitation module is used to connect the in-situ polymer solid-state battery to be tested into the test system and apply an alternating electric field with set parameters to the inside of the battery through the tabs of the solid-state battery. The transceiver module is used to transmit ultrasonic pulses into the solid-state battery and receive the original ultrasonic echo signal that penetrates the solid-state battery while the alternating electric field is applied. The demodulation module is used to demodulate the original ultrasonic echo signal based on the frequency of the alternating electric field using the phase-locked differential principle, and to extract the dynamic perturbation component. The reconstruction module is used to reconstruct and output a three-dimensional spectrum of the polymerization degree and uniformity of the solid electrolyte based on the dynamic perturbation component, combined with spatial coordinate scanning data and a preset correlation model.

9. An electronic device, characterized in that, include: At least one processor; as well as A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor to enable the at least one processor to perform the test method for non-destructive testing of the degree of polymerization and uniformity of solid electrolytes as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the test method for non-destructive testing of the degree of polymerization and uniformity of solid electrolytes as described in any one of claims 1-7.

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