A directional heat-conducting composite solid-state electrolyte and a solid-state battery system thereof

Abstract

The present application relates to the technical field of solid-state lithium battery, and particularly relates to a composite solid-state electrolyte with directional heat conduction and a solid-state battery system thereof, which comprises an inorganic ceramic electrolyte matrix, a directional heat conduction enhancer, a mechanical enhancement network and a multifunctional polymer matrix; the ratio of the thermal conductivity Kz in the thickness direction to the horizontal thermal conductivity Kxy of the composite solid-state electrolyte is not less than 5, and the overall elastic modulus is not greater than 1 GPa. The present application constructs a vertical heat channel by using the core-shell structure directional heat conduction enhancer arranged in the thickness direction, so that the heat is quickly and directionally conducted out; the ceramic nanofiber mechanical enhancement network and the directional heat conduction enhancer are interwoven to form a three-dimensional composite framework, which provides mechanical strength for inhibiting dendrites; the multifunctional polymer matrix is embedded and filled to form an integrated structure and endow the overall flexibility. The problems of heat accumulation, dendrite growth and interface contact loss are solved. The present application solves the contradiction that the existing composite solid-state electrolyte cannot simultaneously have efficient directional heat dissipation, high mechanical strength and good interface flexibility.

Description

Technical Field

[0001] This invention relates to the field of solid-state lithium battery technology, and in particular to a directional thermally conductive composite solid electrolyte and its solid-state battery system. Background Technology

[0002] Solid-state lithium batteries are considered the core of next-generation energy storage technology due to their high energy density and high safety potential. Among them, composite solid-state electrolytes, which combine the high ionic conductivity and mechanical strength of inorganic ceramics with the processing flexibility and interfacial compatibility of organic polymers, have become a research focus.

[0003] However, the design of existing composite solid electrolytes often faces a prominent contradiction: the difficulty in synergistically optimizing thermodynamic and mechanical properties. On the one hand, to improve ionic conductivity and suppress dendrite formation, it is necessary to introduce high-volume-fraction inorganic fillers and construct a continuous network structure. However, this usually sacrifices the flexibility of the material, resulting in an excessively high electrolyte modulus, which makes it impossible to maintain close interfacial contact with the electrode during cycling, leading to contact loss and high interfacial impedance. On the other hand, when using flexible polymer matrices to improve interfacial compatibility, it often sacrifices the mechanical strength and thermal stability of the material, making it particularly difficult to effectively manage the Joule heat and reaction heat generated during battery operation. The isotropic diffusion of heat within the electrolyte easily leads to localized temperature accumulation, accelerating interfacial side reactions and lithium dendrite growth. Conventional randomly distributed thermally conductive fillers cannot achieve directional and rapid heat dissipation.

[0004] Therefore, existing composite solid-state electrolytes struggle to simultaneously achieve efficient directional thermal management, sufficient mechanical strength to suppress dendrites, and good overall flexibility to ensure interface contact within the same system. Designing a composite solid-state electrolyte structure that combines high anisotropic thermal conductivity for rapid directional heat dissipation, high mechanical strength for safety, and appropriate flexibility to maintain interface stability has become a key bottleneck and an urgent technical challenge hindering the development of high-safety, long-life solid-state batteries. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a directional thermally conductive composite solid-state electrolyte and its solid-state battery system. This is achieved by constructing vertical thermal channels through a core-shell structure with directional thermally conductive reinforcements aligned along the thickness direction, enabling rapid and directional heat dissipation. A three-dimensional composite framework is formed by interweaving a ceramic nanofiber mechanical reinforcement network with the directional thermally conductive reinforcements, providing mechanical strength to suppress dendrite formation. A multifunctional polymer matrix is ​​used to embed and fill the system, forming an integrated structure and imparting overall flexibility. This solves the problems of heat accumulation, dendrite growth, and interfacial contact loss. It also resolves the contradiction in existing composite solid-state electrolytes of simultaneously achieving efficient directional heat dissipation, high mechanical strength, and good interfacial flexibility.

[0006] To achieve the above objectives, the present invention provides a directional thermally conductive composite solid electrolyte, comprising:

[0007] Inorganic ceramic electrolyte matrix; A directional thermal conduction enhancer, having a core-shell structure and oriented along the thickness direction of the composite solid electrolyte, constructs a vertical heat conduction channel; The mechanical reinforcement network is made of interwoven ceramic nanofibers and is spatially interwoven and nested with the directional thermally conductive reinforcement to form a three-dimensional composite skeleton with a continuous three-dimensional interpenetrating connection structure. A multifunctional polymer matrix is ​​used to encapsulate the inorganic ceramic electrolyte matrix and together they fill the pores of the three-dimensional composite framework to form an integrated structure. The composite solid electrolyte has a thermal conductivity Kz along the thickness direction to a thermal conductivity Kxy along the horizontal direction of not less than 5, and an overall elastic modulus not greater than 1 GPa.

[0008] Preferably, the mechanical reinforcement network is woven from silicon carbide aerogel fibers or recombinant silk protein biomimetic fibers; The surface of the silicon carbide aerogel fiber or recombinant silk protein biomimetic fiber is coated with a nano-ceramic coating by a sol-gel method.

[0009] Preferably, a portion of the volume of the inorganic ceramic electrolyte matrix is ​​replaced by a biomimetic mineralization material or a porous organic framework polymer with sub-nanometer-scale regular channels. The inner surface of the pores is modified with anionic anchoring groups to construct anisotropic ion transport channels in the three-dimensional interpenetrating interconnect structure.

[0010] Preferably, the composite solid electrolyte has a Janus asymmetric functional gradient structure in the thickness direction, constructed by the sacrificial template method or gradient 3D printing technology; The gradient structure contains pre-embedded sacrificial microspheres or fiber templates that are removed in subsequent processing.

[0011] Preferably, the multifunctional polymer matrix is ​​a simplified two-phase structure formed by the self-assembly of a single type of block copolymer, wherein one phase is a continuous phase that provides ion transport channels and the other phase is a dispersed phase that provides mechanical support; The two phases are connected by physical entanglement or hydrogen bonds between molecular chains.

[0012] Preferably, the composite solid electrolyte contains pre-polarized multiferroic nanofillers or piezoelectric polymer nanofibers. The multiferroic nanofillers or piezoelectric polymer nanofibers induce a continuous lithium-ion-rich space charge layer around the inorganic ceramic electrolyte matrix through ferroelectric / piezoelectric coupling effect or electret effect. The composite solid electrolyte has a microfluidic network and an embedded microelectrode array for online monitoring of electrochemical impedance spectroscopy embedded inside or at the interface with the electrode. The microfluidic network is connected to an external liquid storage tank and pump valve system.

[0013] Preferably, the composite solid electrolyte is a self-supporting flexible film with a thickness of no more than 50 μm; The directional thermally conductive reinforcement also serves as the main mechanical reinforcement phase. The shell of the directional thermally conductive reinforcement core-shell structure is a highly thermally conductive flexible polymer, and the core is a highly thermally conductive ceramic nanowire. The directional thermally conductive reinforcement is oriented in a wavy or spiral shape within the film. The multifunctional polymer matrix is ​​a highly elastic material; The self-supporting flexible film can withstand tensile strain of not less than 50% without breaking, and after 100 tensile cycles, the ionic conductivity retention rate is not less than 90%.

[0014] Preferably, the directional thermally conductive reinforcement and the inorganic ceramic electrolyte matrix together construct a pressure-sensitive permeation network that combines pressure sensitivity and radio frequency identification functions; The pressure-sensitive permeation network is embedded with a miniature passive RFID chip, and the antenna impedance of the miniature passive RFID chip is modulated by the resistance of the pressure-sensitive permeation network.

[0015] On the other hand, a solid-state battery system is also provided, including: A battery cell unit comprising the composite solid electrolyte as described in any one of claims 1-8; An external field excitation module is used to emit ultrasonic or radio frequency radiation of a specific frequency and power to the battery cell unit; The management module is used to monitor the status signals of the battery cell in real time, and control the start-up, shutdown and parameter adjustment of the external excitation module based on preset conditions and the output of the AI ​​algorithm prediction model.

[0016] Preferably, the management module implements the following specific control methods: S1: Status monitoring and data acquisition steps: The management module controls the embedded microelectrode array to apply an AC excitation signal containing multiple characteristic frequency points to the cell unit at a preset period or in response to a trigger event; The management module synchronously acquires the response signal fed back by the embedded microelectrode array, and calculates and generates the electrochemical impedance spectroscopy data of the cell unit in real time based on the AC excitation signal and the response signal. S2: Intelligent diagnosis and risk quantification step. The management module inputs the electrochemical impedance spectroscopy data generated in step S1 into a pre-trained neural network model. The neural network model performs feature extraction and pattern recognition on the electrochemical impedance spectroscopy data and outputs diagnostic results including at least the rate of change of interfacial lithium-ion transport resistance and dendrite risk level. S3: Decision generation and proactive intervention step. Based on the diagnostic results output in step S2, the management module executes at least one of the following intervention instructions: (a) When the diagnostic result indicates that the interface lithium-ion transport resistance increases but does not reach the dendrite high-risk level, the management module generates a first control command; the first control command drives the pump valve system connected to the microfluidic network to inject the lithium salt-containing functional fluid in the storage tank into the corresponding interface area of ​​the cell unit through the microfluidic network; (b) When the diagnostic result indicates that the dendrite risk has reached a high risk level, the management module generates a second control command; the second control command simultaneously drives the pump valve system to inject dendrite suppression functional fluid and starts the external field excitation module to emit ultrasonic or radio frequency radiation with specific parameters to the corresponding area of ​​the battery cell; (c) When the diagnostic result indicates that interface stress accumulates, the management module generates a third control command; the third control command drives the external field excitation module to emit low-power radio frequency radiation to locally raise the temperature of the composite solid electrolyte in order to trigger its internal thermal response shape memory effect. S4: Effect feedback and model optimization steps. After executing the intervention command in step S3, within a preset time period, the management module executes steps S1 to S2 again to obtain the electrochemical impedance spectroscopy data and diagnostic results after the intervention. The management module associates and stores the data before and after the intervention with the parameters of the executed intervention command, and uses it to perform periodic optimization training on the neural network model.

[0017] The beneficial effects of this invention are as follows: Vertical heat channels are constructed by directionally oriented core-shell thermal reinforcements arranged along the thickness direction, enabling rapid directional heat dissipation; a three-dimensional composite framework is formed by interweaving ceramic nanofiber mechanical reinforcement networks with the directional thermal reinforcements, providing mechanical strength to suppress dendrite formation; and an integrated structure is formed by embedding and filling with a multifunctional polymer matrix, imparting overall flexibility. This solves the problems of heat accumulation, dendrite growth, and interfacial contact loss. It also resolves the contradiction in existing composite solid electrolytes that cannot simultaneously achieve efficient directional heat dissipation, high mechanical strength, and good interfacial flexibility. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the microstructure of the composite solid electrolyte of the present invention, which shows the three-dimensional interpenetrating topology at the nanoscale, with a scale bar of 200 nm.

[0019] The reference numerals in the figures include: 1. Inorganic ceramic electrolyte matrix; 2. Directional thermally conductive reinforcement; 3. Mechanical reinforcement network; 4. Multifunctional polymer matrix. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings.

[0021] like Figure 1 As shown, a directional thermally conductive composite solid electrolyte of the present invention comprises: Inorganic ceramic electrolyte substrate 1 serves as a rigid body providing a fast lithium-ion transport channel. It offers high intrinsic ionic conductivity, laying the foundation for high power performance.

[0022] The directional thermally conductive reinforcement 2, with a core-shell structure and oriented along the thickness direction of the composite solid electrolyte, constructs a vertical heat conduction channel. The core-shell structure provides an efficient heat conduction path; the directional arrangement along the thickness direction (Z-axis) creates a preferred vertical heat conduction channel. This guides the heat generated inside the battery to be rapidly discharged along the Z-axis, achieving directional thermal management and preventing heat accumulation on the horizontal plane to form local hot spots. This solves the problem that conventional randomly distributed thermally conductive fillers cannot achieve directional and rapid heat discharge.

[0023] The mechanical reinforcement network 3, composed of interwoven ceramic nanofibers, is spatially interwoven and nested with the directional thermally conductive reinforcement 2, forming a three-dimensional composite skeleton with a continuous three-dimensional interpenetrating connection structure. The high-modulus ceramic nanofibers interweave to form a rigid skeleton, and their interweaving and nesting with the directional thermally conductive reinforcement 2 achieves force-thermal pathway coupling and interlocking. The three-dimensional composite skeleton provides macroscopic mechanical support for the overall structure, suppresses lithium dendrite penetration, and ensures the positional stability of the directional thermally conductive reinforcement 2 under stress, thus solving the problem of weak dendrite suppression ability caused by the mechanical strength of the sacrificial material.

[0024] A multifunctional polymer matrix 4 encapsulates the inorganic ceramic electrolyte matrix 1 and together they fill the pores of the three-dimensional composite framework, forming an integrated structure. The polymer acts as a continuous phase to bond, coat, and fill all the inorganic rigid components. This integrated structure eliminates the macroscopic interfaces between components and reduces ion transport impedance. At the same time, the polymer imparts flexibility to the overall structure, ensuring conformal contact with the electrode and solving the problem of the electrolyte having an excessively high modulus, which prevents it from maintaining a tight interfacial contact with the electrode.

[0025] The ratio of the thermal conductivity Kz along the thickness direction to the thermal conductivity Kxy along the horizontal direction of the composite solid electrolyte is not less than 5. This quantitatively characterizes the degree of anisotropy in heat conduction achieved by the directional arrangement of the directional thermal reinforcement 2. It ensures that the thermal management function has a significant and measurable directional advantage, solving the problems of ineffective heat management and the inability to achieve directional heat extraction.

[0026] The overall elastic modulus of the composite solid electrolyte is no greater than 1 GPa. Quantitative characterization shows that after the synergistic effect of the multifunctional polymer matrix 4 and the three-dimensional composite framework, the macroscopic mechanical properties of the material fall within the flexible range. This ensures that the material possesses the necessary flexibility to adapt to changes in electrode volume and maintain stable interfacial contact, while also taking into account the high internal strength provided by the three-dimensional composite framework. This resolves the contradiction between the difficulty in synergistically optimizing thermodynamic and mechanical properties and the inability to simultaneously achieve sufficient mechanical strength and good overall flexibility.

[0027] During battery operation, the Joule heat and reaction heat generated inside the battery are captured by the inorganic ceramic electrolyte matrix 1 and the interface region. The core-shell structured, directional thermally conductive reinforcement 2, oriented along the thickness direction, forms a preferential heat flow channel perpendicular to the electrode plane, rapidly directing heat to the outside of the battery and effectively suppressing heat diffusion and accumulation in the planar direction. A mechanical reinforcement network 3, formed by interwoven ceramic nanofibers and nested within the directional thermally conductive reinforcement 2, constitutes a three-dimensional composite framework, providing continuous rigid support for the entire electrolyte structure, resisting internal stress, and suppressing dendrite penetration. A multifunctional polymer matrix 4, embedding the inorganic ceramic electrolyte matrix 1 and filling the pores of the three-dimensional composite framework, serves as both a binder and a flexible phase, integrating all components, ensuring the continuity of ion transport, and maintaining close contact with the electrodes through its own flexibility. Ultimately, the composite solid electrolyte exhibits a significantly higher thermal conductivity in the thickness direction than in the horizontal direction, and the overall structure combines high flexibility with high internal rigidity, synergistically achieving efficient directional heat dissipation, dendrite suppression, and interface stability.

[0028] The mechanical reinforcement network 3 in this embodiment is woven from silicon carbide aerogel fibers or recombinant silk biomimetic fibers; utilizing the extremely low density and high specific strength of silicon carbide aerogel fibers, or the high toughness and biomimetic interface properties of recombinant silk biomimetic fibers, mechanical reinforcement is achieved while greatly reducing the weight of the electrolyte (increasing energy density) or introducing excellent biocompatibility and damping properties.

[0029] The surface of silicon carbide aerogel fibers or recombinant silk biomimetic fibers is coated with a nano-ceramic coating via a sol-gel method. This sol-gel method forms a nanoscale ceramic interface layer on the fiber surface. This significantly improves the interfacial compatibility and bonding strength between the fibers and the inorganic ceramic electrolyte matrix 1 and the multifunctional polymer matrix 4, enhances stress transfer efficiency, and prevents interfacial debonding.

[0030] Specifically, the density of silicon carbide aerogel fibers can be ≤0.1 g / cm³. 3 For example, 0.08 g / cm³ 3 Or 0.05g / cm 3 0.08g / cm 3 Or 0.05g / cm 3Its extremely low density ensures the lightweight nature of the entire composite solid electrolyte and provides effective mechanical support and stress dispersion at a low mass.

[0031] The diameter of silicon carbide aerogel fiber monofilaments can be 50-500 nm, such as 100 nm or 300 nm. The diameter scale of 100 nm or 300 nm can ensure that the fiber has sufficient flexural modulus and strength, as well as excellent flexibility and large specific surface area, which is conducive to forming a tight interfacial bond with the polymer matrix.

[0032] The thickness of the nano-ceramic coating can be 5-50 nm, such as 10 nm or 30 nm. A nano-ceramic coating with a thickness of 10 nm or 30 nm can effectively modify the fiber surface, improve its chemical compatibility and wettability with the inorganic ceramic electrolyte matrix 1 and the polymer matrix, thereby enhancing the interfacial bonding strength.

[0033] In this embodiment, a portion of the volume of the inorganic ceramic electrolyte matrix 1 is replaced by a biomimetic mineralization material or a porous organic framework polymer with sub-nanometer-scale ordered channels; the molecularly ordered channels of the above materials are used as confined spaces for ion transport. This introduces additional, structurally ordered ion transport pathways, improving ion selectivity or transport efficiency.

[0034] The inner surface of the pores is modified with anion-anchoring groups to construct anisotropic ion transport channels within a three-dimensional interpenetrating structure. Anions are chemically immobilized on the pore surface. This creates anisotropic ion channels within the three-dimensional interpenetrating structure that hinder anion migration, thereby increasing the lithium-ion transference number and reducing battery polarization.

[0035] Specifically, the biomimetic mineralization material can be selected from calcium silicate hydrate with a regular mesoporous structure; the porous organic framework polymer can be a self-microporous polymer (PIM) with inherent anionic sites.

[0036] The replacement ratio can be 10%-60%, for example, 25% or 50%. A 25% replacement ratio can maintain the main structural integrity of the inorganic ceramic electrolyte matrix 1 while introducing additional ion transport pathways; a 50% replacement ratio makes the ion channel network formed by the framework material dominant, with a more significant anisotropic transport effect. The pore size can be 0.5-1.2 nm, for example, 0.7 nm or 1.0 nm. A pore size of 0.7 nm is close to the size of the lithium-ion solvation shell, which is beneficial for partial desolvation or selective ion transport, increasing the migration number; a pore size of 1.0 nm provides a more spacious and less restrictive transport channel for lithium ions, which helps to achieve higher ionic conductivity.

[0037] The areal density of anionic anchoring groups can be 1-10 groups / nm. 2 For example, 3groups / nm2 or 8groups / nm 2 3groups / nm 2 The areal density provides sufficient fixed anion sites on the pore surface, effectively hindering anion migration; 8 groups / nm 2 The areal density can strongly anchor anions, which is expected to bring the lithium-ion transference number close to or greater than 0.8.

[0038] Anisotropy can be represented by the ratio of the migration energy barriers of lithium ions along the thickness and horizontal directions within the channel, E_a(vertical) / E_a(horizontal), which is 1.5-5.0, for example, a ratio of 2.0 or 4.0. A ratio of 2.0 indicates that ion migration in the thickness direction is twice as difficult as in the horizontal direction, and a clear anisotropic transport can be constructed; a ratio of 4.0 indicates strong anisotropy, which can more effectively "guide" or "constrain" ion transport in a specific direction.

[0039] The composite solid electrolyte of this embodiment has a Janus asymmetric functional gradient structure in the thickness direction, constructed by the sacrificial template method or gradient 3D printing technology. Through gradient design, the electrolyte exhibits an asymmetric composition and performance distribution on both sides in the thickness direction. This allows the two sides of the electrolyte to adapt to the different interface requirements of the positive and negative electrodes (e.g., the positive electrode side requires high strength constraint, and the negative electrode side requires high deformation tolerance).

[0040] In this process, sacrificial microspheres or fiber templates are pre-embedded within the gradient structure and removed during subsequent processing. The templates occupy space, and their removal creates a controllable pore gradient. The density distribution of sacrificial bonds (high porosity on the negative electrode side favors sacrificial bond enrichment) and the density distribution of the mechanically reinforced network 3 (low porosity on the positive electrode side favors dense packing) within the gradient structure are precisely controlled, thereby programmatically constructing the Janus performance gradient.

[0041] Specifically, the sacrificial template can be polystyrene microspheres or thermally degradable fibers. The sacrificial bond density ρ_sb(Z) can decrease exponentially or linearly along the thickness direction (Z-axis), for example, satisfying ρ_sb(0)≥2. ρ_sb(L), where 0 represents the negative electrode side and L represents the positive electrode side. ρ_sb(0)≥2 The relationship of ρ_sb(L) ensures that the sacrificial bond density on the negative electrode side is at least twice that on the positive electrode side, thereby giving the interface region on the negative electrode side a multiplied enhanced deformation absorption and stress dissipation capability, effectively buffering the volume changes and stress caused by lithium deposition / stripping.

[0042] The density ρ_f(Z) of the mechanically reinforced network can increase exponentially or linearly, for example, satisfying ρ_f(L)≥1.8. ρ_f(0), where 0 represents the negative electrode side and L represents the positive electrode side. ρ_f(L)≥1.8 The relationship between ρ_f(0) ensures that the density of the mechanical reinforcement network 3 on the positive electrode side is at least 1.8 times that on the negative electrode side, providing stronger constraints and support for the structural expansion and oxygen release of high-nickel and other positive electrode materials during cycling. The entire gradient is a continuous gradient, and the spatial rate of change |dρ / dZ| is greater than 0 and monotonically changes within the thickness range.

[0043] In this embodiment, the multifunctional polymer matrix 4 is a simplified two-phase structure formed by the self-assembly of a single type of block copolymer. One phase is a continuous phase providing ion transport channels, and the other phase is a dispersed phase providing mechanical support. The two phases are connected by physical entanglement or hydrogen bonds between molecular chains. Utilizing the microphase separation characteristics of block copolymers, self-assembly forms a continuous phase (ion channels) and a dispersed phase (mechanical support) with nanoscale phase separation. This simplifies the composition of the polymer matrix while achieving nanoscale fine partitioning of ion transport and mechanical support functions, improving the material's uniformity and stability.

[0044] Specifically, the block copolymer can be selected from poly(styrene-ethylene-butene-styrene) (SEBS) grafted lithium salt or polyethylene oxide-polypropylene oxide (PEO-PPO) block copolymer. The macroscopic elastic modulus of the matrix can be 0.05 GPa-0.5 GPa, for example 0.1 GPa or 0.3 GPa. The modulus of 0.1 GPa makes the composite solid electrolyte very soft, which can form excellent conformal contact with the electrode and adapt to volume changes during cycling; the modulus of 0.3 GPa provides higher mechanical support and puncture resistance while maintaining good flexibility, which is beneficial for suppressing dendrite penetration.

[0045] The composite solid electrolyte of this embodiment contains pre-polarized multiferroic nanofillers or piezoelectric polymer nanofibers. Multiferroic nanofillers or piezoelectric polymer nanofibers induce a continuous lithium-ion-rich space charge layer around the inorganic ceramic electrolyte matrix 1 through ferroelectric / piezoelectric coupling effect or electret effect.

[0046] By utilizing the persistent built-in electric field (ferroelectric / piezoelectric / electret effect) of the polarized filler / fiber, a lithium-ion-rich space charge layer is induced around the inorganic ceramic electrolyte matrix 1, selectively promoting lithium-ion transport, significantly increasing the lithium-ion transference number (t_Li+≥0.7), and optimizing battery kinetic performance.

[0047] Specifically, the multiferroic filler can be bismuth ferrite (BiFeO3); the piezoelectric polymer nanofibers can be polyvinylidene fluoride (PVDF) or its copolymer nanofibers. Polarization treatment can be achieved through thermal polarization or corona polarization.

[0048] The space charge layer thickness δ_SCL can be 2-20 nm, for example 5 nm or 15 nm. A thickness of 5 nm is sufficient to form a significant lithium-ion enrichment region near the interface between the ferroelectric filler and the ceramic matrix; a thickness of 15 nm can extend the enrichment effect to a wider area.

[0049] The lithium-ion transference number t_Li+ can be ≥0.7, for example, 0.75 or 0.85. A lithium-ion transference number of 0.75 can significantly reduce battery polarization and improve power performance and cycle stability; a lithium-ion transference number of 0.85 is close to the level of a single-ion conductor, which can greatly suppress concentration polarization and improve high-rate performance and low-temperature performance.

[0050] In this embodiment, a microfluidic network and an embedded microelectrode array for online monitoring of electrochemical impedance spectroscopy are embedded inside the composite solid electrolyte or at the interface with the electrode. The microfluidic network connects to external liquid storage tanks and pump / valve systems; Microfluidic networks are used to transport functional fluids; embedded microelectrode arrays are used for online acquisition of electrochemical impedance spectroscopy data. This enables in-situ, online monitoring and active intervention of the internal state of the electrolyte. The microfluidic network can be driven by micro-peristaltic pumps or piezoelectric micropumps, and the start / stop and flow rate are controlled by a pump-valve system (such as micro-solenoid valves) to transport the functional fluid from the reservoir to the designated location.

[0051] The walls of the microfluidic network may be made of inert polymer materials (such as polyimide, PDMS) or a dense ceramic / polymer composite layer integrally formed with the electrolyte matrix to ensure chemical stability and mechanical strength.

[0052] In terms of preparation, techniques such as sacrificial template method (e.g., pre-embedded soluble fibers), microimprinting, or high-precision 3D printing can be used to simultaneously construct the network during the electrolyte molding process.

[0053] Specifically, the channel width of the microfluidic network can be 10-100 μm, such as 30 μm, 50 μm, or 70 μm. A width of 30 μm allows for more precise fluid control and faster response; a width of 70 μm provides higher fluid flux, suitable for rapid injection of large volumes of functional fluids; and a width of 50 μm provides fluid flux between 30 μm and 70 μm.

[0054] The electrode spacing of embedded microelectrode arrays can be 50-200 μm, such as 100 μm or 150 μm. A 100 μm spacing enables local impedance measurement with higher spatial resolution; a 150 μm spacing reduces the complexity and cost of the electrode array while still effectively monitoring the overall impedance change trend over a larger area.

[0055] The electrochemical impedance spectroscopy (EIS) test frequency range can be 0.1 Hz–1 MHz. The neural network model can be a convolutional neural network (CNN), which is used to analyze the impedance spectrum in real time, realizing integrated closed-loop management of "sensing-diagnosis-treatment".

[0056] The composite solid electrolyte in this embodiment is a self-supporting flexible film with a thickness of no more than 50 μm; through ultra-thin design, the volumetric energy density of the battery is greatly improved, making it suitable for flexible electronic devices.

[0057] The directional thermally conductive reinforcing material 2 also serves as the main mechanical reinforcing phase. The shell of the directional thermally conductive reinforcing material 2 core-shell structure is a highly thermally conductive flexible polymer, and the core is a highly thermally conductive ceramic nanowire. The directional thermally conductive reinforcing material 2 is oriented in a wave-like or spiral shape within the film. The multifunctional polymer matrix 4 is a highly elastic material. The self-supporting flexible film can withstand tensile strain of not less than 50% without breaking, and after 100 tensile cycles, the ionic conductivity retention rate is not less than 90%.

[0058] The thermally conductive reinforcement is endowed with intrinsic flexibility and stretchability, and deformation space is reserved through wave / spiral orientation. This allows the film to withstand significant stretching (≥50%) without damage while maintaining directional thermal conductivity and reinforcement functions, enabling stretchable electronic applications.

[0059] Specifically, the thickness of the self-supporting flexible film can be 10-50 μm, such as 20 μm or 40 μm. A thickness of 20 μm can minimize the volume and weight of inactive materials in the battery, greatly improving energy density; a thickness of 40 μm provides higher mechanical robustness while maintaining good flexibility. The high thermal conductivity flexible polymer shell can be selected from silver-filled polyurethane or polysiloxane; the high elastomer matrix can be selected from hydrogenated styrene-butadiene-styrene block copolymer (SEBS).

[0060] The ionic conductivity of the self-supporting flexible film at 25℃ is not less than 1×10⁻⁶. -4 S / cm. Tensile strain can be 50% or 100%. 50% tensile strain can accommodate common deformations such as human joint bending and textile stretching; 100% tensile strain represents an extremely high elastic limit and can be applied to extremely stretchable electronic devices.

[0061] In this embodiment, the directional thermally conductive reinforcement 2 and the inorganic ceramic electrolyte matrix 1 together construct a pressure-sensitive permeation network that combines pressure sensitivity and radio frequency identification (RFID) functions. A miniature passive RFID chip is embedded in the pressure-sensitive permeation network, and the antenna impedance of the miniature passive RFID chip is modulated by the resistance of the pressure-sensitive permeation network. Conductive fillers are dispersed at the interface or within the matrix constructed from the directional thermally conductive reinforcement 2 and the inorganic ceramic electrolyte matrix 1 to form a pressure-sensitive permeation network. The resistance of the permeation network changes with pressure, and a miniature passive RFID chip is integrated. This wirelessly and passively converts internal stress changes in the battery (such as dendrite growth and volume expansion) into remotely readable electrical signals, enabling intelligent wireless monitoring of the battery's mechanical state.

[0062] Pressure-sensitive permeation networks can have multiple conductive filler ratio schemes under different technical approaches, all expressed as the total integral (vol%) in the composite solid electrolyte: Option 1: Carbon-based nanomaterial-dominated type (suitable for high sensitivity and lightweight applications) Conductive filler: Multi-walled carbon nanotubes (MWCNTs) and graphene nanosheets (GNPs) are combined.

[0063] Specific proportions: MWCNT: 0.8 vol% - 1.2 vol% GNP: 0.5 vol% - 1.0 vol% Total: 1.3 vol% - 2.2 vol% Technical effects: Carbon nanotubes and graphene sheets synergistically construct a three-dimensional conductive network with abundant contact points, significant piezoresistive effect, high sensitivity, and low density.

[0064] Option 2: Metal nanoparticle-dominated type (suitable for high stability and fast response) Conductive filler: a composite of silver nanowires (AgNW) and silver-coated ceramic microspheres.

[0065] Specific proportions: AgNW: 0.5 vol% - 1.0 vol% Silver-coated alumina microspheres: 3.0 vol% - 5.0 vol% Total: 3.5 vol% - 6.0 vol% Technical effects: Silver nanowires form the backbone network, and the coated microspheres provide reliable contact points. The network has good stability, excellent conductivity, and strong oxidation resistance.

[0066] Option 3: Hybrid (balancing performance and cost) Conductive fillers: conductive carbon black (CB), nickel-plated graphene, and short-cut carbon fibers.

[0067] Specific proportions: Conductive carbon black (CB): 2.0 vol% - 3.0 vol% Nickel-plated graphene: 0.3 vol% - 0.7 vol% Short-cut carbon fiber: 0.5 vol% - 1.0 vol% Total: 2.8 vol% - 4.7 vol% Technical benefits: Carbon black ensures the formation of a basic percolation network, nickel-plated graphene enhances conductivity and interfacial bonding, and chopped carbon fibers strengthen the network's mechanical stability and expand the sensing range.

[0068] Specifically, the miniature passive RFID chip size can be ≤1mm x 1mm, for example, 0.8mm x 0.8mm. The operating frequency can be 13.56MHz or the UHF band (e.g., 915MHz). The wireless reading distance can be 1-10cm, for example, 3cm or 7cm. The volume fraction φ of the conductive filler in the pressure-sensitive permeation network is located near its permeation threshold φ_c, satisfying 0.9φ_c ≤ φ ≤ 1.1φ_c. Within a pressure range of 0.1-10MPa, the stress detection sensitivity S = (ΔR / R0) / Δσ ≥ 0.05 MPa. -1 Where σ is the mechanical stress (in MPa) on the pressure-sensitive permeation network, and R0 is the initial resistance under zero pressure, for example, 0.1 MPa. -1 0.1MPa -1 Its high sensitivity enables the system to clearly identify minute pressure changes caused by lithium deposition, volume expansion, or external compression, achieving early warning.

[0069] Example 1 The specific parameters of each component and the preparation method of the directional thermally conductive composite solid electrolyte of this embodiment are as follows: 1. Composition and parameters of inorganic ceramic electrolyte matrix 1: Selected from Li7La3Zr2O 12 (LLZO, tetragonal phase), prepared by solid-state reaction method, sintered at 1150℃ for 6 hours. The particles exhibit an irregular polyhedral morphology, with a D50 of 1.2 μm (measured by laser particle size analyzer) and a specific surface area of ​​8.5 m². 2 / g (determined by BET method), tap density 1.8g / cm³ 3 The surface was modified with 0.5 wt% KH-550 silane coupling agent, with a grafting rate of 1.2 wt% (determined by thermogravimetric analysis), to improve interfacial compatibility with the polymer matrix.

[0070] 2. Structure and parameters of the directional thermally conductive reinforcement 2: The core-shell structure is adopted, with boron nitride nanowires (BN NWs) having a diameter of 50±10nm, a length of 5±2μm, an aspect ratio of 100±30, and a thermal conductivity of about 300W / (m·K); the shell is a polysiloxane (PDMS-based) with a thickness of 10±3nm and a thermal conductivity of 0.2W / (m·K), which gives the core flexibility and interfacial adhesion.

[0071] Orientation parameters: Vertically aligned along the thickness direction (Z-axis), with a density of 200 strands / mm. 2 (Scanning electron microscopy statistics) Arrangement >85% (X-ray diffraction pole figure determination). The total integral of the core-shell structure is 15 vol%, of which the core accounts for 10 vol and the shell accounts for 5 vol.

[0072] 3. Composition and interweaving method of mechanical reinforcement network 3: It uses silicon carbide aerogel fiber (SiC AF) with a density of 0.08 g / cm³. 3 The single filaments have a diameter of 200±50 nm and a length of 50-200 μm. The surface is coated with an Al2O3 nano-ceramic coating by a sol-gel method, with a thickness of 15±5 nm (measured by transmission electron microscopy) and a coating density >90%.

[0073] Interlacing method: Fibers are randomly intertwined to form a three-dimensional network structure with an areal density of 0.5 mg / cm³. 2 The porosity is 75% (measured by mercury porosimetry). The interweaving of fibers and directional thermally conductive reinforcement 2: BN NWs penetrate vertically through the fiber network plane, and at the contact point, they form Si-O-Al chemical bonds with the PDMS shell through the Al2O3 nano-ceramic coating (XPS confirmed), realizing the coupling and interlocking of the mechanical-thermal pathway.

[0074] 4. Two-phase structure of multifunctional polymer matrix 4: Lithium TFSI was grafted onto SEBS (polystyrene-ethylene-butene-styrene) with a molecular weight of 80,000. The LiTFSI content was [EO] / [Li] + =12. A two-phase structure was formed by self-assembly via solution casting-evaporation: the continuous phase is a PEO-rich phase (ion transport channel), with a volume fraction of 55% and a phase region channel width of 30-80 nm (measured by small-angle X-ray scattering); the dispersed phase is a PS-hard phase (mechanical support), with a volume fraction of 25% and a particle diameter of 50-150 nm.

[0075] The two phases are physically entangled between molecular chains (entanglement density 0.05 chains / nm). 3 ) and hydrogen bonds (hydrogen bond density 2.5 × 10 20 bonds / cm 3(Infrared spectroscopy measurement) connection. The macroscopic elastic modulus of the matrix is ​​0.2 GPa (nanoindentation measurement).

[0076] 5. Preparation method: S1: Mix LLZO powder (50 vol%), BN NWs@PDMS core-shell structure (15 vol%), SiC AF (10 vol%), and SEBS-LiTFSI solution (25 vol% solid content), and add LiTFSI lithium salt (relative to SEBS [EO] / [Li)). + The mixture of 12) and TPO photoinitiator (1wt%) was ball-milled and dispersed for 2 hours to obtain a uniform slurry.

[0077] S2: Inject the slurry into the mold and apply a steady magnetic field of 0.5T (perpendicular to the film surface) for 30 minutes to induce the directional alignment of BN NWs; at the same time, apply a DC electric field of 5kV / cm for 10 minutes to assist in lithium salt dissociation and ion channel pre-orientation.

[0078] S3: UV curing (wavelength 365nm, intensity 50mW / cm²) 2 (Time: 10 min) In-situ polymerization is used to form a multifunctional polymer matrix and construct a three-dimensional interpenetrating connection structure.

[0079] S4: Hot-pressed integrated assembly (temperature 80℃, pressure 2MPa, time 30min), assembled with LiFePO4 cathode and lithium metal anode to form a solid-state battery.

[0080] 6. Performance test results:

[0081] Example 2 This embodiment provides a directional thermally conductive composite solid electrolyte with a Janus asymmetric functional gradient structure, which focuses on optimizing the different performance requirements of the positive and negative electrode sides.

[0082] 1. Janus gradient structure design: A functional gradient along the thickness direction (Z-axis) was constructed using a sacrificial template method combined with gradient 3D printing technology. The total thickness of the electrolyte is 100 μm, divided into the positive electrode side (Z=L, 0-50 μm) and the negative electrode side (Z=0, 50-100 μm).

[0083] Sacrifice template parameters: Negative electrode side (high porosity / high sacrificial bond density): polystyrene microspheres (PS spheres), diameter 3±0.5μm, volume fraction 25%, distribution density ρ_sb(0)=0.35g / cm³ 3 .

[0084] Positive electrode side (low porosity / low sacrificial bond density): Polylactic acid (PLA) fibers, diameter 10±2μm, volume fraction 8%, distribution density ρ_sb(L)=0.15g / cm³ 3 .

[0085] Gradient function: ρ_sb(Z) = ρ_sb(0)·exp(-0.8Z / L), where Z is the distance from the negative electrode side and L=100μm.

[0086] Mechanically reinforced network density gradient: Negative electrode side: SiC AF areal density 0.3 mg / cm³ 2 Porosity 85%.

[0087] Positive electrode side: SiC AF surface density 0.6 mg / cm³ 2 Porosity 65%.

[0088] The gradient function is: ρ_f(Z) = ρ_f(0)·[1+0.9(Z / L)], which satisfies ρ_f(L)=1.9ρ_f(0)>1.8ρ_f(0).

[0089] 2. Gradient 3D printing process: Multi-head direct ink writing is used, with the following parameters: Nozzle diameter: 300μm (negative electrode side) → 200μm (positive electrode side); Printing speed: 20mm / s (negative side) → 30mm / s (positive side); Layer thickness: 50μm / layer, 2 layers in total; Slurry solids content gradient: 40 vol% (negative electrode side) → 55 vol% (positive electrode side); Post-printing heat treatment: 350℃ / 2h to remove PS template (thermal decomposition), 400℃ / 1h to remove PLA fiber template, heating rate 2℃ / min, nitrogen protection.

[0090] 3. Performance Comparison:

[0091] Compared with symmetrical structures: When the battery is assembled with NCM811 positive electrode and lithium metal negative electrode, after 300 cycles at 1C, the interface impedance growth on the positive electrode side is reduced by 42%, and the risk of lithium dendrite puncture on the negative electrode side is reduced by 65% ​​(observed by in-situ optical microscopy).

[0092] Example 3 This embodiment provides a directional thermally conductive composite solid electrolyte containing pre-polarized multiferroic nanofillers, which enhances the lithium-ion transference number through a built-in electric field.

[0093] 1. Parameters of multiferroic nanofillers: Bismuth ferrite (BiFeO3) nanoparticles with a perovskite structure, a particle size of 80±20 nm, and a tetragonal phase content >90% (XRD determination) were selected. The room temperature ferroelectric polarization intensity Pr = 45 μC / cm 2 (Hysteresis loop measurement).

[0094] Pre-polarization process: thermal polarization method, temperature 110℃, DC electric field strength 120kV / cm, polarization time 60min, residual polarization intensity Prr after polarization = 38μC / cm 2 (>80% retention rate).

[0095] 2. Construction of the space charge layer: The polarized BiFeO3 particles were uniformly dispersed in the LLZO matrix at an addition amount of 2.5 vol%, distributed in the interstices between the LLZO particles. Through the interaction between the ferroelectric depolarization field (depolarization factor N≈0.3) and the oxygen vacancies on the LLZO surface, a lithium-rich space charge layer was induced to form around the LLZO particles.

[0096] Space charge layer parameters (measured by electrochemical strain microscopy): Thickness δ_SCL: 8±2nm.

[0097] Local lithium-ion concentration: 5 times higher than that in bulk.

[0098] Ionic conductivity within the space charge layer: 8 times higher than that of the bulk layer.

[0099] 3. Performance improvement effect:

[0100] Example 4 This embodiment provides a directional thermally conductive composite solid electrolyte integrated microfluidic network, an embedded microelectrode array, and an AI management module, applied in a battery where the microfluidic network connects to an external storage tank and pump / valve system. The storage tank stores functional fluids, including lithium salt-containing functional fluids and dendrite-inhibiting functional fluids.

[0101] 1. Microfluidic network integration technology: The sacrificial template method is used for preparation. Specific steps are as follows: (a) Pre-embedded soluble polyvinyl alcohol (PVA) fibers, 50±10μm in diameter, are randomly distributed in the slurry (same as the slurry in step S1 of Example 1) by electrospinning, with a fiber volume fraction of 5%; (b) Electrolyte forming (same as steps S2-S3 in Example 1); (c) Water washing and dissolution: Soak in deionized water for 2 hours, then use ultrasound assistance for 10 minutes to remove PVA and form flow channels; (d) Secondary encapsulation of the flow channel wall: Inject PDMS prepolymer (10:1 ratio), cure at 80℃ for 30 min to form a sealing layer with a wall thickness of 100±20μm; Microfluidic network parameters: Flow channel width: 50μm, flow channel density: 20 channels / mm 2 ; The total volume of the flow channel as a percentage of the electrolyte volume is 3%. Pressure resistance: >0.5MPa (air tightness test); 2. Embedded microelectrode array: Electrode material: platinum wire, 25 μm in diameter, arranged in a 5×5 matrix, with an electrode spacing of 150 μm. An Al2O3 insulating layer with a thickness of 100 nm is deposited on the electrode surface by ALD, with only the probe end (200 μm in length) exposed.

[0102] Integration process: After step (c), a platinum wire is inserted into the flow channel, and silver conductive paste (80% solid content) is injected to fix and conduct the circuit. It is then cured at 80°C for 1 hour. The wire is led out through a PDMS sealed interface (1 mm in diameter) and connected to an external EIS acquisition system.

[0103] EIS test parameters: frequency range 0.1Hz-1MHz, 10 frequency points / decades, AC amplitude 10mV, test cycle once every 10 minutes.

[0104] 3. AI Management Module Architecture: Neural network model: Input: EIS data (complex impedance Z', Z'', 20-dimensional features in total).

[0105] Network structure: 3-layer CNN (Conv1D, 3 convolutional kernels, 32-64-128 channels) + 2 fully connected layers (256-64 nodes) + Softmax output layer.

[0106] Output: Change rate of interfacial lithium-ion transport resistance (0-100%), dendrite risk level (0-3, 0=normal, 3=high risk), interfacial stress accumulation index (0-10).

[0107] Training data: 1200 sets of labeled data (including four categories: normal, early degradation, dendrite growth, and precursors of thermal runaway), 80% training set / 20% test set.

[0108] Performance metrics: Accuracy 96.5%, false positive rate 3.2%, false negative rate 1.8%, single-sample inference time 85ms.

[0109] 4. AI management module proactive intervention control logic

[0110] Post-intervention feedback: EIS test was performed again after 30 minutes to compare the changes in impedance spectrum before and after the intervention. The data was stored in the database for incremental model training (updated monthly).

[0111] 5. System verification results: Compared with a control battery without an AI management module (NCM811 / Li, 1C charge / discharge): Early dendrite detection time: 45 hours in advance (verified by optical microscope). Interface impedance growth rate: decreased by 58%; Cycle life: increased from 450 cycles to 780 cycles (capacity retention of 80%). Thermal runaway warning success rate: 100% (10 overcharge trigger tests).

[0112] Example 5 This embodiment provides a directional thermally conductive composite solid electrolyte, which is a self-supporting stretchable flexible film with a thickness of 20 μm, suitable for flexible batteries in flexible / wearable electronic devices.

[0113] 1. Thin film structure parameters: Total thickness: 20±2μm (measured with a micrometer). Surface density: 2.5 mg / cm³ 2 ; Directional thermally conductive reinforcement: It also serves as the main mechanical reinforcement phase, employing a BN NWs@polyurethane (PU) core-shell structure.

[0114] BN NWs: Diameter 30nm, length 3μm, thermal conductivity 280W / (m·K); PU shell: 8nm thickness, 50MPa modulus, elongation at break >300%; Orientation: Wavy, amplitude 8 μm, wavelength 25 μm (measured by atomic force microscopy) Volume fraction: 12 vol%.

[0115] 2. Highly elastic matrix: Hydrogenated styrene-butadiene-styrene block copolymer (SEBS, Kraton G1652) was selected, with a molecular weight of 70,000 and a styrene content of 30 wt%. Paraffin oil plasticizer (30 wt%) was added, resulting in a matrix modulus of 0.08 GPa and an elongation at break of >500%.

[0116] 3. Tensile property test:

[0117] 4. Flexible battery demonstration: With LiFePO4 cathode (area density 10 mg / cm³) 2 A flexible solid-state battery is assembled with a lithium foil anode (50μm) and a lithium foil negative electrode (450μm), resulting in a total thickness of 450μm. Battery performance: 0.5C discharge capacity: 155 mAh / g (based on cathode mass).

[0118] Bending test: After bending 1000 times with a radius of R=5mm, the capacity retention rate is >95%.

[0119] Dynamic stretching test: 20% strain dynamic stretching (simulating skin movement), 100 cycles, volume retention rate >90%.

[0120] Example 6 This embodiment provides a wireless monitoring composite solid electrolyte that integrates a pressure-sensitive permeation network and a miniature passive RFID chip.

[0121] 1. Pressure-sensitive permeation network formulation (Option 1: Carbon-based nanomaterial-dominated type):

[0122] Dispersion process: First, MWCNT and GNP are ultrasonically dispersed in NMP for 2 hours (power 300W), then mixed with electrolyte slurry and ball-milled for 1 hour to ensure that the conductive filler is distributed in the interface region between the directional thermally conductive reinforcement 2 and the LLZO matrix.

[0123] 2. Percolation network performance: Zero-voltage resistance R0: 150kΩ (measured using the four-probe method); Seepage threshold φ_c: 1.5 vol% (inflection point of the resistance-volume fraction curve); Pressure detection range: 0.1-10MPa; Sensitivity S = (ΔR / R0) / Δσ: 0.12 MPa -1 (Linear region 0.5-5MPa); Response time: <50ms (pressure step response); Cyclic stability: >2000 cycles (0-5MPa cycle, resistance drift <10%).

[0124] 3. RFID Integration Solution: Chip model: EM4325 (EM Microelectronic), passive UHF RFID, EPC Gen2 protocol Chip size: 0.8mm × 0.8mm × 0.2mm Operating frequency: 915MHz Antenna design: Dipole antenna (16cm long, etched on aluminum foil), connected in series with a varistor network. Antenna impedance modulation: The change in the resistance ΔR of the varistor network causes a change in the antenna Q value, and the change in the backscattered signal intensity ΔP / P0≈0.3(ΔR / R0) Wireless reading distance: 5cm (RFID reader power 30dBm) 4. Pressure-wireless signal calibration:

[0125] Application scenarios: Real-time monitoring of lithium metal anode volume expansion (corresponding to pressure 0.5-2MPa), early identification of local stress concentration caused by dendrite growth (>3MPa is the warning threshold).

[0126] On the other hand, a solid-state battery system is also provided, including: The battery cell unit includes the aforementioned composite solid electrolyte; The external field excitation module is used to emit ultrasonic or radio frequency radiation of specific frequencies and powers into the battery cell. Utilizing the energy penetration of ultrasonic / radio frequency radiation, it provides non-contact energy input to the electrolyte. It can remotely and actively trigger intelligent behaviors such as thermal response and shape memory within the electrolyte, or provide thermal energy to improve interface transmission, achieving dynamic regulation of the battery state. Specifically, the external field excitation module can use a near-infrared laser emitter of a specific wavelength as the light radiation source, with power and irradiation time precisely controlled by the management module; or it can use a Helmholtz coil or an electromagnet of a specific structure to generate an alternating magnetic field, with frequency and intensity adjustable by the management module through a drive circuit.

[0127] The management module monitors the status signals of the battery cells in real time and controls the start / stop and parameter adjustment of the external excitation module based on preset conditions and the output of the AI ​​algorithm prediction model. It introduces AI prediction and decision-making, upgrading external intervention from passive response to proactive management based on prediction, preemptively suppressing dendrite growth or repairing interface defects, and achieving intelligent preventative maintenance. The core of the management module can be a microcontroller unit responsible for scheduling and running pre-trained neural network models (such as TensorFlow Lite models stored in memory) and controlling peripheral circuits.

[0128] Specifically, the ultrasonic frequency can be 20 kHz–1 MHz, such as 100 kHz or 500 kHz, and the sound intensity can be 0.1–5 W / cm². 2 For example, 1W / cm 2 100kHz ultrasound has good penetration and moderate energy density; 1W / cm² 2The sound intensity can provide effective thermal or mechanical vibration effects without damaging materials.

[0129] The radio frequency radiation frequency can be 433MHz or 2.45GHz, and the power density can be 10–200mW / cm². 3 For example, 50mW / cm 3 Radio frequency radiation of 2.45 GHz can generate dielectric heating in media containing polar molecules or ions, achieving rapid and uniform temperature rise.

[0130] The preset trigger conditions can be that the relative rate of change of resistance ΔR / R0 exceeds the threshold θ_R (e.g., 10% or 15%), or the temperature reaches the warning value T_alert (e.g., 50℃).

[0131] A relative rate of change of resistance ΔR / R0 exceeding 10% typically corresponds to significant deterioration of interfacial contact; the temperature warning value of 50℃ is set before the common upper limit of safe temperature to allow response time for active thermal management.

[0132] AI algorithm prediction models can predict dendrite growth trends or hotspot locations based on historical data.

[0133] The AI ​​algorithm prediction model includes a deep learning-based neural network model, which is selected from one or more of convolutional neural networks, recurrent neural networks, graph neural networks, Transformer, and combinations thereof.

[0134] In a preferred embodiment, the neural network model is a three-layer one-dimensional convolutional neural network. The input is complex impedance data of electrochemical impedance spectroscopy, and the output includes the rate of change of interfacial lithium-ion transport resistance, dendrite risk level, and interfacial stress accumulation index.

[0135] The management module implements the following specific control methods: S1: Status monitoring and data acquisition steps: The management module controls the embedded microelectrode array to apply an AC excitation signal containing multiple characteristic frequency points to the cell unit at a preset cycle or in response to a trigger event; The management module synchronously acquires the response signal fed back by the embedded microelectrode array, and calculates and generates the electrochemical impedance spectroscopy data of the cell unit in real time based on the AC excitation signal and the response signal. S2: Intelligent diagnosis and risk quantification step. The management module inputs the electrochemical impedance spectroscopy data generated in step S1 into the pre-trained neural network model. The neural network model performs feature extraction and pattern recognition on the electrochemical impedance spectroscopy data and outputs diagnostic results including at least the rate of change of interface lithium-ion transport resistance and dendrite risk level. S3: Decision generation and proactive intervention steps. Based on the diagnostic results output in step S2, the management module executes at least one of the following intervention instructions: (a) When the diagnostic results indicate that the interface lithium-ion transport resistance has increased but has not reached the dendrite high-risk level, the management module generates a first control command; the first control command drives the pump valve system connected to the microfluidic network to inject the lithium salt functional fluid in the storage tank into the corresponding interface area of ​​the cell unit through the microfluidic network. (b) When the diagnostic results indicate that the dendrite risk has reached a high risk level, the management module generates a second control command; the second control command simultaneously drives the pump valve system to inject dendrite suppression fluid and starts the external field excitation module to emit ultrasonic or radio frequency radiation with specific parameters to the corresponding area of ​​the cell unit. (c) When the diagnostic results indicate that interface stress is accumulating, the management module generates a third control command; the third control command drives the external field excitation module to emit low-power radio frequency radiation to locally raise the temperature of the composite solid electrolyte in order to trigger its internal thermal response shape memory effect. S4: Effect feedback and model optimization steps. After executing the intervention command in step S3, within a preset time period, the management module executes steps S1 to S2 again to obtain the electrochemical impedance spectroscopy data and diagnostic results after the intervention. The management module associates and stores the data before and after the intervention with the parameters of the executed intervention command, and uses it to periodically optimize and train the neural network model.

[0136] A pressure-sensitive permeation network is constructed by connecting a directional thermally conductive reinforcing element 2 to an inorganic ceramic electrolyte matrix 1, converting stress into a resistance signal. Electrochemical impedance spectroscopy data is acquired using an embedded microelectrode array. The management module analyzes the data using a pre-trained neural network model, diagnoses risks, and generates instructions. This achieves real-time, in-situ monitoring and intelligent diagnosis of internal battery stress and interface conditions. Based on diagnostic results (such as dendrite risk level), the management module can precisely control the injection of functional fluids (such as dendrite inhibitors) into the microfluidic network and / or activate an external field excitation module (emitting light radiation or alternating magnetic fields at specific frequencies) for coordinated intervention, completing a closed-loop management system from "sensing" to "treatment," significantly improving battery reliability and lifespan.

[0137] Specifically, the preparation method of the composite solid electrolyte includes the following steps: S1: Disperse the inorganic ceramic electrolyte matrix or its precursor, directional thermally conductive reinforcement, fibrous reinforcement and functional factors to form a slurry or precursor network; S2: By applying an external physical field and / or using template method and gradient forming technology, the directional arrangement of components in the slurry or precursor network is induced, and the prototype of Janus asymmetric functional gradient structure and three-dimensional composite skeleton is constructed simultaneously or stepwise. S3: Introduce a monomer system into the prototype of the three-dimensional composite skeleton, and form the multifunctional polymer matrix through in-situ polymerization and cross-linking reaction to complete the construction of the three-dimensional interpenetrating connection structure; S4: Integrate the obtained composite electrolyte structure with the electrode.

[0138] In S1, when an inorganic ceramic electrolyte matrix precursor is used, it can be mixed with a polymerizable monomer solvent to form a curable slurry. The solid content of the slurry can be 30-60 vol%, for example, 40 vol% or 55 vol%; or an organic framework precursor and a polymerizable monomer can be used to prepare a flexible precursor network.

[0139] In S2, the external physical field can be a steady-state magnetic field of 0.1-1T (e.g., 0.5T) or a DC electric field of 1-10kV / cm (e.g., 5kV / cm), used to induce directional alignment and optional in-situ polarization.

[0140] Gradient forming techniques include layered casting, multi-nozzle printing, or sacrificial template methods.

[0141] In S3, polymerization can be carried out by ultraviolet light, thermal initiation, etc., and the temperature can be 40-100℃, such as 60℃ or 80℃. For the technical route using a flexible precursor network, it can include impregnation of inorganic precursor and subsequent segmented heat treatment steps, such as removing the template at 150℃, partially carbonizing the organic framework at 500℃, and crystallizing and sintering the inorganic precursor at 750℃.

[0142] In S4, integrated integration can be achieved through an in-situ co-curing process, with pressure ranging from 0.1 to 10 MPa (e.g., 2 MPa or 8 MPa) and temperature ranging from 60 to 150°C (e.g., 100°C).

[0143] Summary of key parameters for preparation method:

[0144] The above description is only a preferred embodiment of the present invention. For those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present invention. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. A directional thermally conductive composite solid electrolyte, characterized in that, include: Inorganic ceramic electrolyte matrix (1); The directional thermal conduction enhancer (2) has a core-shell structure and is oriented along the thickness direction of the composite solid electrolyte to construct a vertical heat conduction channel; The mechanical reinforcement network (3) is woven from ceramic nanofibers and is spatially interwoven and nested with the directional thermally conductive reinforcement (2) to form a three-dimensional composite skeleton with a continuous three-dimensional interpenetrating connection structure. A multifunctional polymer matrix (4) is used to encapsulate the inorganic ceramic electrolyte matrix (1) and fill the pores of the three-dimensional composite skeleton to form an integrated structure. The composite solid electrolyte has a thermal conductivity Kz along the thickness direction to a thermal conductivity Kxy along the horizontal direction of not less than 5, and an overall elastic modulus not greater than 1 GPa.

2. The composite solid electrolyte according to claim 1, characterized in that, The mechanical reinforcement network (3) is woven from silicon carbide aerogel fibers or recombinant silk protein biomimetic fibers; The surface of the silicon carbide aerogel fiber or recombinant silk protein biomimetic fiber is coated with a nano-ceramic coating by a sol-gel method.

3. The composite solid electrolyte according to claim 1, characterized in that, Part of the volume of the inorganic ceramic electrolyte matrix (1) is replaced by a biomimetic mineralization material or a porous organic framework polymer with sub-nanometer-scale regular channels. The inner surface of the pores is modified with anionic anchoring groups to construct anisotropic ion transport channels in the three-dimensional interpenetrating interconnect structure.

4. The composite solid electrolyte according to claim 1 or 2, characterized in that, The composite solid electrolyte has a Janus asymmetric functional gradient structure in the thickness direction, constructed by the sacrificial template method or gradient 3D printing technology. The gradient structure contains pre-embedded sacrificial microspheres or fiber templates that are removed in subsequent processing.

5. The composite solid electrolyte according to claim 1 or 3, characterized in that, The multifunctional polymer matrix (4) is a simplified two-phase structure formed by the self-assembly of a single type of block copolymer, wherein one phase is a continuous phase that provides ion transport channels and the other phase is a dispersed phase that provides mechanical support. The two phases are connected by physical entanglement or hydrogen bonds between molecular chains.

6. The composite solid electrolyte according to claim 1 or 2, characterized in that, The composite solid electrolyte contains pre-polarized multiferroic nanofillers or piezoelectric polymer nanofibers. The multiferroic nanofillers or piezoelectric polymer nanofibers induce a continuous lithium-ion-rich space charge layer around the inorganic ceramic electrolyte matrix (1) through ferroelectric / piezoelectric coupling effect or electret effect. The composite solid electrolyte has a microfluidic network and an embedded microelectrode array for online monitoring of electrochemical impedance spectroscopy embedded inside or at the interface with the electrode. The microfluidic network is connected to an external liquid storage tank and pump valve system.

7. The composite solid electrolyte according to claim 1, characterized in that, The composite solid electrolyte is a self-supporting flexible film with a thickness of no more than 50 μm; The directional thermally conductive reinforcement (2) also serves as the main mechanical reinforcement phase. The shell of the directional thermally conductive reinforcement (2) core-shell structure is a highly thermally conductive flexible polymer, and the core is a highly thermally conductive ceramic nanowire. The directional thermally conductive reinforcement (2) is wavy or spiral oriented within the film. The multifunctional polymer matrix (4) is a highly elastic material; The self-supporting flexible film can withstand tensile strain of not less than 50% without breaking, and after 100 tensile cycles, the ionic conductivity retention rate is not less than 90%.

8. The composite solid electrolyte according to claim 1, characterized in that, The directional thermally conductive reinforcement (2) and the inorganic ceramic electrolyte matrix (1) together construct a pressure-sensitive permeation network that combines pressure sensitivity and radio frequency identification functions; The pressure-sensitive permeation network is embedded with a miniature passive RFID chip, and the antenna impedance of the miniature passive RFID chip is modulated by the resistance of the pressure-sensitive permeation network.

9. A solid-state battery system, characterized in that, include: A battery cell unit comprising the composite solid electrolyte as described in any one of claims 1-8; An external field excitation module is used to emit ultrasonic or radio frequency radiation of a specific frequency and power to the battery cell unit; The management module is used to monitor the status signals of the battery cell in real time, and control the start-up, shutdown and parameter adjustment of the external excitation module based on preset conditions and the output of the AI ​​algorithm prediction model.

10. The solid-state battery system according to claim 9, characterized in that, The management module implements the following specific control methods: S1: Status monitoring and data acquisition steps, the management module controls the embedded microelectrode array to apply an AC excitation signal containing multiple characteristic frequency points to the cell unit at a preset period or in response to a triggering event; The management module synchronously collects the response signal fed back by the embedded microelectrode array, and calculates and generates the electrochemical impedance spectroscopy data of the cell unit in real time based on the AC excitation signal and the response signal. S2: Intelligent diagnosis and risk quantification step. The management module inputs the electrochemical impedance spectroscopy data generated in step S1 into a pre-trained neural network model. The neural network model performs feature extraction and pattern recognition on the electrochemical impedance spectroscopy data and outputs diagnostic results including at least the rate of change of interfacial lithium-ion transport resistance and dendrite risk level. S3: Decision generation and proactive intervention step. Based on the diagnostic results output in step S2, the management module executes at least one of the following intervention instructions: (a) When the diagnostic result indicates that the interface lithium-ion transport resistance increases but does not reach the dendrite high-risk level, the management module generates a first control command; the first control command drives the pump valve system connected to the microfluidic network to inject the lithium salt-containing functional fluid in the storage tank into the corresponding interface area of ​​the cell unit through the microfluidic network; (b) When the diagnostic result indicates that the dendrite risk has reached a high risk level, the management module generates a second control command; the second control command simultaneously drives the pump valve system to inject dendrite suppression functional fluid and starts the external field excitation module to emit ultrasonic or radio frequency radiation with specific parameters to the corresponding area of ​​the battery cell; (c) When the diagnostic result indicates that interface stress accumulates, the management module generates a third control command; the third control command drives the external field excitation module to emit low-power radio frequency radiation to locally raise the temperature of the composite solid electrolyte in order to trigger its internal thermal response shape memory effect. S4: Effect feedback and model optimization steps. After executing the intervention command in step S3, within a preset time period, the management module executes steps S1 to S2 again to obtain the electrochemical impedance spectroscopy data and diagnostic results after the intervention. The management module associates and stores the data before and after the intervention with the parameters of the executed intervention command, and uses it to perform periodic optimization training on the neural network model.

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