Array type flexible temperature and pressure integrated sensor, preparation method thereof and detection system

Abstract

The application discloses an array type flexible temperature and pressure integrated sensor, a preparation method thereof and a detection system, and comprises a flexible bearing substrate, a bottom conductive electrode, a force-sensitive / temperature-sensitive composite functional matrix, an insulating separation medium, a top conductive electrode and a surface encapsulation protective layer. The application initiates a double-process synergy of negative pressure liquid phase penetration assembly combined with a transient gas phase foaming process, constructs a multi-stage interconnected mesoporous nanoskeleton in the temperature-sensitive and force-sensitive functional layer, and replaces the traditional single blending dense forming structure. Through the composite structure of material particle ordered arrangement + uniform mesoporous pore, the problems of conductive particle agglomeration, sheet stacking and conductive path occlusion are solved, a continuous, uniform and highly stable three-dimensional conductive network is constructed, technical pain points of sensor response lag, performance drift and cycle attenuation are eliminated from the micro level, and the structural stability and service life of the sensing material are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of flexible sensor technology, specifically to an array-type flexible temperature and pressure integrated sensor, its preparation method, and detection system. Background Technology

[0002] With the rapid iteration of the electric vehicle industry, the safety of power battery packs has become a core concern for the industry's development. During long-term charge-discharge cycles, extreme environmental conditions (high temperature, low temperature, collision), and aging, power batteries are prone to safety hazards such as abnormal internal temperature rise, sudden pressure changes caused by cell expansion, and short circuits caused by external punctures. If timely, comprehensive, and high-precision monitoring and early warning cannot be achieved, serious safety accidents such as thermal runaway, fire, or even explosion can easily occur.

[0003] Currently, monitoring technologies for power battery packs have several limitations: First, temperature monitoring often uses single-point thermistors (NTCs), which can only detect the temperature at a single point, resulting in large monitoring blind spots and failing to cover all cells and gap areas. Second, temperature and pressure sensors are mostly designed separately, resulting in large and thick volumes with poor flexibility, making it difficult to fit the complex curved surfaces of the battery pack and occupying valuable space. Third, existing pressure sensors often use a single electrode and a single layer of pressure-sensitive material, resulting in low pressure detection sensitivity, difficulty in capturing minute pressure changes inside the battery pack, and weak anti-interference capabilities, making them susceptible to external environmental influences. Fourth, some integrated temperature and pressure sensors have not optimized the layout of electrodes and functional layers, leading to mutual interference between temperature and pressure detection signals, making it difficult to meet the stringent requirements of power battery packs in terms of detection accuracy.

[0004] To address the aforementioned technical deficiencies, a flexible sensor array based on a multi-level interconnected mesoporous nanoframework structure, integrating temperature and pressure, large-area detection, high sensitivity, and strong anti-interference capability, as well as an integrated monitoring system based on this sensor, has significant practical implications and industrial value for improving the safety performance of electric vehicle power battery packs and ensuring driving safety. Summary of the Invention

[0005] The technical problem solved by this invention is to provide an array-type flexible temperature and pressure integrated sensor, its preparation method, and detection system.

[0006] The technical solution adopted by this invention to solve its technical problem is: An array-type flexible temperature and pressure integrated sensor includes: a flexible support substrate as mechanical support; a bottom conductive electrode disposed above the flexible support substrate; a force-sensitive functional matrix integrated on the upper surface of the bottom conductive electrode; an insulating separator covering the force-sensitive functional matrix; an upper force-sensitive response layer vertically aligned with the force-sensitive functional matrix; a top conductive electrode located at the upper end of the upper force-sensitive response layer; a temperature-sensitive functional matrix integrated on the lower surface of the top conductive electrode and uniformly distributed with the upper force-sensitive response layer on the lower surface of the top conductive electrode in an alternating lattice pattern; and a surface encapsulation protective layer for overall protection. The force-sensitive functional matrix and its upper force-sensitive response layer form an array of force-sensitive sensing units, and the temperature-sensitive functional matrix forms an array of temperature-sensitive sensing units. The force-sensitive sensing units and the temperature-sensitive sensing units are evenly distributed in an alternating lattice pattern between the top conductive electrode and the bottom conductive electrode to form a force-sensitive / temperature-sensitive composite functional matrix, which completely covers the surface of the flexible bearing substrate to achieve ultra-large area full-domain synchronous monitoring. The flexible support substrate, the bottom conductive electrode, the force-sensitive / temperature-sensitive composite functional matrix, the insulating separator, the top conductive electrode, and the surface encapsulation protective layer are then encapsulated in an integrated stacked structure from bottom to top.

[0007] Furthermore, both the force-sensitive sensing unit and the temperature-sensitive sensing unit are prepared using a dual-process synergistic approach combining negative pressure liquid-phase permeation assembly with transient gas-phase foaming molding. Inside the force-sensitive sensing unit and the temperature-sensitive sensing unit, a multi-level interconnected mesoporous nanoframework of 50nm-200nm is constructed, forming a multi-level interconnected flexible three-dimensional porous network structure.

[0008] Furthermore, the temperature-sensitive sensing unit includes a temperature-sensitive composite material, which includes a flexible polymer and temperature-sensitive material particles. The flexible insulating polymer includes one or more composite systems of PDMS and PI, and the temperature-sensitive material particles include one or more composite systems of carbon nanotubes, graphene, and metal nanoparticles. The force-sensitive sensing unit includes a pressure-sensitive composite material, which includes an elastic substrate and pressure-sensitive material particles. The elastic substrate includes one or more compound systems of PDMS and PU, and the pressure-sensitive material particles include one or more compound systems of graphene and MXene.

[0009] Furthermore, both the bottom conductive electrode and the top conductive electrode are equipped with no less than four conductive paths, which are arranged in a longitudinal and transverse intersecting manner to form a cross-shaped electrode array and form n×m intersection points, providing conductive paths for the acquisition of pressure and temperature dual signals; the force-sensitive sensing unit is arranged at the intersection of the bottom conductive electrode and the top conductive electrode.

[0010] Furthermore, the force-sensitive sensing unit includes a first-layer force-sensitive sensing unit and a second-layer force-sensitive sensing unit arranged vertically. The first-layer force-sensitive sensing unit is integrated on the upper surface of the bottom conductive electrode as the force-sensitive functional matrix; the second-layer force-sensitive sensing unit serves as the upper force-sensitive response layer and is integrated on the lower surface of the top conductive electrode. The insulating separating medium is disposed around the force-sensitive sensing unit and is tightly attached to the force-sensitive sensing unit, surrounding the first-layer force-sensitive sensing unit and the second-layer force-sensitive sensing unit in the force-sensitive sensing unit, forming a two-phase sensing structure with upper and lower alignment, thus constituting a two-phase force-sensitive sensing unit.

[0011] Furthermore, the surface encapsulation protective layer has a hollowed-out area corresponding to each temperature-sensitive sensing unit, with the hollowed-out size being less than or equal to the size of the temperature-sensitive sensing unit, forming a hollowed-out area of ​​the protective layer; the area corresponding to each force-sensitive sensing unit is raised by thin film stacking.

[0012] Furthermore, an ultra-thin thermally conductive protective coating is printed within the hollowed-out area of ​​the protective layer.

[0013] A method for fabricating an array-type flexible temperature and pressure integrated sensor includes the following steps: S1: Preparation of flexible load-bearing substrate: Flexible insulating materials such as PDMS, PI, or PU are selected and prepared by spin coating to obtain a flexible load-bearing substrate; S2: Preparation of bottom conductive electrode: Select silver-based electrode or MXene-based composite conductive electrode as bottom conductive electrode material, print it on the upper surface of flexible support substrate by screen printing, or form it on the upper surface of flexible support substrate by vacuum evaporation process, arrange at least four longitudinal conductive paths, and obtain bottom conductive electrode after constant temperature curing. S3: Preparation of insulating separation medium: Liquid insulating epoxy adhesive is selected as the insulating separation medium material. According to the size, position and distribution of the force-sensitive sensing unit, precise hollow coating is carried out. The mask plate fixed point forming process is adopted, and the hollow size is reserved. After the coating is completed, it is pre-cured at low temperature for later use. S4. Preparation of the first-layer force-sensitive sensing unit: Using PDMS elastomer or PU elastomer as the base material, add 6%-8% graphene or MXene as pressure-sensitive material particles, and add an appropriate amount of dispersant. After mixing evenly, ultrasonically disperse to obtain the first-layer pressure-sensitive composite material. Subsequently, the first-layer pressure-sensitive composite material is printed on the surface of the bottom conductive electrode by screen printing. After isothermal curing, an array-type force-sensitive sensing unit is formed. Finally, through the synergistic process of negative pressure liquid phase infiltration assembly technology combined with transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm-200nm is constructed to form a uniform and interconnected flexible three-dimensional conductive porous structure. S5. Preparation of secondary force-sensitive sensing units: The preparation process is consistent with that of the first-layer force-sensitive sensing unit. Corresponding to the size, position and distribution of the first-layer force-sensitive sensing unit, the second-layer force-sensitive sensing unit is printed on the surface of the top conductive electrode by screen printing. The second-layer force-sensitive sensing unit is constructed by combining the negative pressure liquid phase infiltration assembly technology with the transient gas phase foaming molding process. S6. Preparation of temperature-sensitive sensing units: Using flexible polymers such as PDMS or PI as the base material, add 5wt%-6wt% of one or more composite systems of carbon nanotubes, graphene, or metal nanoparticles as temperature-sensitive conductive particles, and add an appropriate amount of dispersant. After mixing evenly, ultrasonically disperse to obtain a temperature-sensitive composite material. Subsequently, the temperature-sensitive composite material is printed onto the surface of the top conductive electrode by screen printing. It is evenly distributed on the surface of the top conductive electrode in an alternating lattice with the secondary force-sensitive sensing unit. After printing, it is cured at a constant temperature to form an array-type temperature-sensitive sensing unit. Finally, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm-200nm is constructed inside the unit by using negative pressure liquid phase infiltration assembly technology combined with transient gas phase foaming molding process. S7. Preparation of top conductive electrode: The preparation process is the same as that of bottom conductive electrode. It is prepared on the upper surface of the secondary force-sensitive sensing unit and temperature-sensitive sensing unit by screen printing. At least four transverse conductive paths are set and correspond one-to-one with the vertical electrodes of the bottom conductive electrode. After printing, the electrode leads are fixed by conductive copper foil to ensure close contact with the secondary force-sensitive sensing unit and temperature-sensitive sensing unit, with a contact resistance ≤5Ω. S8: Assembly: The pre-cured liquid insulating epoxy adhesive is used to separate the medium, ensuring that its hollowed-out area is precisely aligned and bonded to the first-layer force-sensitive sensing unit, and then bonded to the upper surface of the flexible support substrate; strictly ensure that the hollowed-out area is completely aligned with the first-layer force-sensitive sensing unit, without offset or obstruction; then, ensure that the second-layer force-sensitive sensing unit is aligned vertically with the first-layer force-sensitive unit in the hollowed-out area of ​​the insulating separator, and after tightly bonding the second-layer force-sensitive unit to the upper surface of the insulating separator, it is cured at a constant temperature to allow the liquid insulating epoxy adhesive to fully cure, forming a biphase force-sensitive sensing unit with a multi-level interconnected mesoporous nanoframework; S9. Preparation of surface encapsulation protective layer: PI film or PET film is selected as the surface encapsulation protective layer material. The area corresponding to each temperature-sensitive sensing unit is hollowed out, and the hollowed-out size is less than or equal to the size of the temperature-sensitive sensing unit. The area corresponding to each biphasic force-sensitive sensing unit is raised by film stacking. Then, the surface encapsulation protective layer is covered on the top conductive electrode through the bonding process of adhesive products and bonded and fixed to the flexible support substrate to ensure tight bonding without bubbles or wrinkles, thus completing the overall preparation of the sensor. Steps S5-S7 are fabricated sequentially. First, a secondary force-sensitive sensing unit and a temperature-sensitive sensing unit are fabricated on the surface of the release material. Then, a top conductive electrode is fabricated on the upper surface of the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit. Alternatively, a top conductive electrode is fabricated on the surface of the release material first, and then a secondary force-sensitive sensing unit and a temperature-sensitive sensing unit are fabricated on the upper surface of the top conductive electrode. Subsequently, the fabricated release material unit is bonded to the upper end of the insulating separator, ensuring that the secondary force-sensitive sensing unit and the primary force-sensitive sensing unit are aligned vertically in the hollowed-out area of ​​the insulating separator. Finally, the release material is removed to transfer the top conductive electrode. Alternatively, a secondary force-sensitive sensing unit and a temperature-sensitive sensing unit can be directly fabricated on the upper end of the insulating separating medium, and a top conductive electrode can be fabricated on the upper surface of the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit.

[0014] Furthermore, the negative pressure liquid phase permeation assembly technology combined with transient gas phase foaming molding process includes the following steps: S11: Screen printing of sensing materials: Thermosensitive composite materials or pressure-sensitive composite materials are regularly printed on the surface of the bottom conductive electrode or the top conductive electrode in an interlaced matrix pattern using a screen. S12: Negative pressure liquid phase infiltration assembly: First, a negative pressure liquid phase infiltration assembly process is adopted. Under negative pressure, the conductive particles inside the temperature-sensitive composite material are driven to arrange themselves in an orderly manner along the liquid phase infiltration direction, breaking the disordered agglomeration state of the material and initially forming an interwoven and interconnected nano-conductive pathway; the pressure-sensitive composite material enables the conductive materials of graphene and MXene two-dimensional sheet materials to overlap and vertically connect in an orderly manner through negative pressure infiltration, constructing a high-density conductive network; S13: Transient vapor phase foaming molding: Through the transient vapor phase foaming molding process, the temperature-sensitive composite material utilizes a small amount of foaming agent to generate gas instantaneously and form microbubbles during the isothermal curing process, generating a mesoporous structure with uniform pore size and interconnection inside the material, forming a multi-level interconnected mesoporous nanoskeleton; the pressure-sensitive composite material also uses a small amount of foaming agent to generate gas instantaneously and form microbubbles during the isothermal curing process, forming uniform mesoporous pores inside the elastic substrate, with the pores and conductive network nested together to form a multi-level interconnected mesoporous nanoskeleton.

[0015] A monitoring system for an array-type flexible temperature and pressure integrated sensor includes the aforementioned array-type flexible temperature and pressure integrated sensor, a signal acquisition module, a signal processing module, a data storage module, an early warning module, and a power supply module. The modules are connected to each other via wires or wireless communication to achieve comprehensive and real-time monitoring of the status of the power battery pack. The array-type flexible temperature and pressure integrated sensor, as the core monitoring component of the system, is fitted and installed on the surface or inside the gap of the power battery pack. The signal acquisition module is connected to the bottom conductive electrode and the top conductive electrode of the sensor, and is used to acquire the resistance change signal of the temperature-sensitive sensing unit and the resistance change signal of the force-sensitive sensing unit in real time. The signal processing module receives the resistance change signal transmitted by the signal acquisition module, performs filtering, amplification, and analog-to-digital conversion on the signal, converts the resistance change signal into identifiable and analyzable temperature and pressure data, and identifies the puncture risk based on the abrupt change characteristics of the pressure and temperature data. The data storage module is used to store the temperature and pressure data output by the signal processing module; The early warning module is electrically connected to the signal processing module. The system presets a temperature threshold, a pressure threshold, and a puncture judgment threshold. When the monitored data exceeds the judgment threshold, the early warning module issues an early warning signal. The power supply module provides a stable power supply for the entire monitoring system.

[0016] The beneficial effects of this invention are: 1. Microstructural Innovation, Completely Solving the Inherent Defects of Traditional Sensing Materials: This invention pioneers a dual-process synergy combining negative pressure liquid-phase infiltration assembly with transient gas-phase foaming technology. This constructs a multi-level interconnected mesoporous nanoframework within the temperature-sensitive and force-sensitive functional layers, replacing the traditional single-blended dense molding structure. Through the composite structure of ordered particle arrangement and uniform mesoporous pores, it solves problems such as conductive particle agglomeration, layer stacking, and conductive path blockage, constructing a continuous, uniform, and highly stable three-dimensional conductive network. This eliminates the technical pain points of sensor response hysteresis, performance drift, and cyclic decay at the microscopic level, significantly improving the structural stability and service life of the sensing material.

[0017] 2. Optimized Structure, Integrated Temperature and Pressure Sensing with No Blind Spots: The sensor adopts an integrated stacked structure consisting of a flexible support substrate, bottom conductive electrode, force / temperature sensitive composite functional matrix, insulating separator, upper force-sensitive response layer, top conductive electrode, and surface encapsulation protective layer. A perforated insulating separator is added to ensure stable bonding and insulation of the dual-phase force-sensitive sensing units while maintaining effective contact between the two layers. The temperature-sensitive functional unit and the dual-phase force-sensitive sensing unit are arranged in an interlocking matrix pattern, completely covering the surface of the flexible support substrate, enabling simultaneous detection of the entire large area of ​​the power battery pack. Simultaneously, it integrates temperature and pressure sensing functions, eliminating the need for separate installation of the two sensors, simplifying the installation process and saving battery pack space.

[0018] 3. High pressure sensitivity and accurate, stable detection: Utilizing the elastic deformation characteristics of a multi-level interconnected mesoporous nanoframework, combined with a crisscrossing electrode array, a biphase force-sensitive alignment structure, and a hollowed-out insulating medium, it can accurately capture minute pressure changes within the 0-10MPa range, with a pressure measurement error ≤ ±0.1MPa. The porous framework can buffer repeated pressure cycle stress, with performance degradation ≤5% after 5000 cycles, exhibiting excellent resilience. The insulating isolation structure, combined with optimized micro-conductive networks, completely eliminates interlayer signal crosstalk, significantly improving detection accuracy and stability.

[0019] 4. Strong anti-interference capability, no cross-coupling in temperature and pressure detection: The differentiated hollow-out padding design of the surface encapsulation, the staggered electrode arrangement, and the spacing of the temperature-sensitive unit, combined with the stable conductivity of the nano-framework, effectively isolate pressure, temperature, and environmental interference. The temperature-sensitive functional unit has a resistance drift of ≤2% in a wide temperature range of -40℃ to 120℃, a temperature measurement error of ≤±1℃, and a temperature resistance change of ≤1% under pressure. There is no signal cross-interference, making it suitable for monitoring complex operating conditions of battery packs.

[0020] 5. Excellent flexibility and strong adaptability to various operating conditions: The multi-level mesoporous nanoframework possesses excellent mechanical buffering properties. Combined with a fully flexible material system, the sensor can be bent to a radius of curvature of 5mm. After 1000 bends, the resistance change is ≤3%, with no delamination or peeling. The insulating medium and the porous sensing layer work together to maintain flexibility, perfectly conforming to the complex curved surface of the battery pack. At the same time, it can withstand alternating high and low temperatures and closed aging conditions, making its adaptability to extreme environments far superior to traditional dense sensors.

[0021] 6. The monitoring system is comprehensive and highly practical: The monitoring system built on this sensor integrates signal acquisition, processing, storage, and early warning functions. It can monitor the temperature and pressure changes of the battery pack in real time, accurately identify cell overheating, cell expansion, and puncture risks, with a response speed of ≤1s and timely and reliable early warning. The data can be traced back for a long time, providing complete data support for battery pack fault analysis and life assessment.

[0022] 7. Simple preparation process and easy to scale up: The dual-process synergistic preparation of nanoframeworks is based on mature processes such as screen printing, negative pressure assembly, and low-temperature foaming. It does not require precision micro-nano processing equipment, has low preparation cost and good consistency, and can realize the mass production of large-area array sensors, which has high industrial promotion value. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the sensor structure of the present invention; Figure 2 This is a cross-sectional structural diagram of an embodiment of the sensor of the present invention; Figure 3 This is a module unit diagram of the sensor monitoring system of the present invention; Figure 4 This is a planar schematic diagram showing the distribution of the bottom conductive electrode and the first layer of force-sensitive sensing material in the sensor of the present invention. Figure 5 This is a planar schematic diagram showing the distribution of the top conductive electrode and the secondary force-sensitive and temperature-sensitive sensor materials in the sensor of the present invention. Figure 6 for Figure 4 and Figure 5 A schematic diagram of the combined plan; Figure 7 for Figure 2 A structural diagram showing the addition of certain components; Figure 8 This is a cross-sectional structural schematic diagram of another embodiment of the sensor of the present invention; Figure 9 This is a pressure performance characteristic curve of the sensor of the present invention; Figure 10 This is a characteristic curve of the temperature-sensitive performance of the sensor in this invention; in: 1. Flexible bearing substrate; 2. Bottom conductive electrode; 3. Force-sensitive sensing unit; 31. First-layer force-sensitive sensing unit; 32. Second-layer force-sensitive sensing unit; 4. Insulating separation medium; 5. Temperature-sensitive sensing unit; 6. Top conductive electrode; 7. Surface encapsulation protective layer; 701. Protective layer cutout area; 702. Encapsulation layer padding; 8. Adhesive layer; 9. Thermally conductive protective coating. Detailed Implementation

[0024] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] like Figure 1-2 As shown, this invention provides an array-type flexible temperature and pressure integrated sensor, comprising: a flexible support substrate 1 for mechanical support; a bottom conductive electrode 2 disposed above the flexible support substrate; a force-sensitive functional matrix integrated on the upper surface of the bottom conductive electrode; an insulating separating medium 4 covering the force-sensitive functional matrix; an upper force-sensitive response layer aligned with the force-sensitive functional matrix; a top conductive electrode 6 located above the upper force-sensitive response layer; a temperature-sensitive functional matrix integrated on the lower surface of the top conductive electrode 6 and distributed in an alternating lattice pattern with the upper force-sensitive response layer on the lower surface of the top conductive electrode 6; and a surface encapsulation protective layer 7 for overall protection. The force-sensitive functional matrix and its upper force-sensitive response layer form a force-sensitive sensing unit 3, and the temperature-sensitive functional matrix forms a temperature-sensitive sensing unit 5. The force-sensitive sensing unit 3 and the temperature-sensitive sensing unit 5 are arranged in an alternating lattice pattern between the top conductive electrode 6 and the bottom conductive electrode 2, forming a force-sensitive / temperature-sensitive composite functional matrix.

[0027] Furthermore, the flexible support substrate 1, the bottom conductive electrode 2, the force-sensitive / temperature-sensitive composite functional matrix, the insulating separator 4, the top conductive electrode 6, and the surface encapsulation protective layer 7 are arranged in an integrated stacked structure with stacked encapsulation from bottom to top.

[0028] like Figures 3-5As shown, both the bottom conductive electrode 2 and the top conductive electrode 6 are equipped with at least four parallel conductive paths, and the electrode bodies are made of flexible conductors. The conductive paths on the bottom conductive electrode 2 and the top conductive electrode 6 are arranged in a crisscross pattern, thereby forming n×m intersection points for deploying the force-sensitive sensing unit 3.

[0029] Furthermore, such as Figure 3 and Figure 4 As shown, in one embodiment, the bottom conductive electrode 2 extends longitudinally, and the top conductive electrode 6 extends laterally. In another embodiment, the bottom conductive electrode 2 extends laterally, and the top conductive electrode 6 extends longitudinally. In other embodiments, the top conductive electrode 2 and the top conductive electrode 6 can also be arranged in a mutually inclined and intersecting configuration, thereby forming several intersection points for arranging the force-sensitive sensing unit 3.

[0030] like Figure 2 and Figure 5 As shown, the force / temperature-sensitive composite functional matrix can completely cover the surface of the flexible support substrate 1, enabling synchronous detection over an ultra-large area. The force-sensitive sensing unit 3 includes a first-layer force-sensitive sensing unit 31 and a second-layer force-sensitive sensing unit 32 arranged vertically. The first-layer force-sensitive sensing unit 31 is integrated on the upper surface of the bottom conductive electrode 2, serving as the force-sensitive functional matrix; the second-layer force-sensitive sensing unit 32 serves as the upper force-sensitive response layer, integrated on the lower surface of the top conductive electrode 6.

[0031] The insulating separator 4 is disposed around the force-sensitive sensing unit and is tightly fitted to it, surrounding and aligning the first-layer force-sensitive sensing unit 31 and the second-layer force-sensitive sensing unit 32 vertically. The first-layer force-sensitive sensing unit 31 and the second-layer force-sensitive sensing unit 32 are vertically aligned and distributed in the hollow area in the middle of the insulating separator 4. Under external pressure, the upper and lower layers of force-sensitive sensing units can achieve controllable contact through the hollow area of ​​the insulating separator 4, thereby outputting differentiated resistance response signals to achieve accurate identification of pressure amplitude and distribution.

[0032] like Figure 2 As shown, the flexible support substrate 1 is made of flexible polymer substrate, including but not limited to: polydimethylsiloxane (PDMS), polyimide (PI), or polyurethane (PU), with an overall thickness controlled between 10-200 μm. This substrate has excellent bending compliance, wide temperature range stability (-40℃~120℃), and chemical inertness, enabling conformal bonding with the complex shape of the power battery pack, meeting the installation adaptation requirements of battery packs with different configurations, and providing stable mechanical support for the overall sensing components.

[0033] Furthermore, the bottom conductive electrode 2 is disposed on the upper surface of the flexible support substrate 1 and can be formed on the substrate surface by screen printing or vacuum evaporation. It is prepared using a flexible conductor, preferably a silver-based electrode or an MXene-based composite conductive electrode. Among them, the MXene-based electrode has high conductivity, structural flexibility, and environmental corrosion resistance, making it more suitable for long-term service scenarios of power battery packs. The bottom conductive electrode 2 contains no less than four conductive paths, each path is uniformly arranged in the longitudinal direction, the electrode width is 0.1–10 mm, the spacing between adjacent longitudinal electrodes is 50–500 μm, and the electrode thickness is controlled between 1–36 μm.

[0034] Furthermore, the force-sensitive sensing unit 3 and the temperature-sensitive sensing unit 5 are integrally formed on the surfaces of the bottom conductive electrode 2 and the top conductive electrode 6 respectively by screen printing. The two are arranged in an alternating and uniform array on the surfaces of the bottom conductive electrode 2 and the top conductive electrode 6 in an interlocking dot matrix form. This can achieve full-area gapless coverage of the flexible bearing substrate surface and realize an ultra-large area composite sensing array, providing all-round and blind-spot-free status monitoring for the power battery pack.

[0035] Furthermore, the first-layer force-sensitive sensing unit 31 is printed on the upper surface of the bottom conductive electrode 2, and the second-layer force-sensitive sensing unit 32 is printed on the lower surface of the top conductive electrode 6. The first-layer force-sensitive sensing unit 31 and the second-layer force-sensitive sensing unit 32 form a vertically aligned dual-phase sensing structure, constituting a dual-phase force-sensitive sensing unit. The temperature-sensitive sensing unit 5 is printed on the lower surface of the top conductive electrode 6, and at least one set of dual-phase force-sensitive sensing units is arranged between adjacent temperature-sensitive sensing units.

[0036] The first-layer force-sensitive sensing unit is tightly bonded to the bottom conductive electrode, and the second-layer force-sensitive sensing unit is tightly bonded to the top conductive electrode. An insulating separator lies between them, forming a stacked sensing structure of "bottom conductive electrode – first-layer force-sensitive sensing unit – insulating separator – second-layer force-sensitive unit – top conductive electrode". When a pressure load is generated inside the battery pack, the biphase force-sensitive sensing unit deforms and makes contact through the hollowed-out area, thereby outputting a differentiated resistance signal. The change in resistance can accurately reflect the magnitude and spatial distribution of the pressure.

[0037] Furthermore, both the first-layer force-sensitive sensing unit 31 and the second-layer force-sensitive sensing unit 32 are made of pressure-sensitive composite material, composed of an elastic substrate and pressure-sensitive material particles. The elastic substrate is preferably, but not limited to, PDMS or PU elastomer, possessing excellent resilience and structural flexibility. The pressure-sensitive material particles are selected from one or more blends of graphene and MXene, and the pressure response sensitivity can be adjusted by the filler ratio. The thickness of the biphase force-sensitive sensing unit is controlled between 2-100 μm.

[0038] Furthermore, the insulating separator 4 is tightly bonded to the periphery of the biphase force-sensitive sensing unit, creating a dedicated pressure-sensing contact channel (cutout area) for the force-sensitive sensing unit. The insulating separator 4 ensures that under external loads, the upper and lower pressure-sensitive composite materials can achieve rapid and effective contact response through the cutout area; the non-cutout area relies on a dense insulating adhesive layer to achieve complete electrical isolation, significantly reducing interlayer signal crosstalk and further improving the accuracy of pressure detection and long-term anti-interference capability. The insulating separator is preferably formed using liquid insulating epoxy adhesive, with a thickness controlled between 5-200μm. After curing, it combines good flexibility, insulation performance, and adhesive strength, enabling stable bonding and electrical isolation between the first-layer force-sensitive sensing unit 31 and the second-layer force-sensitive sensing unit 32, avoiding signal crosstalk in non-sensing areas.

[0039] Furthermore, the temperature-sensitive sensing unit 5 is printed on the lower surface of the top conductive electrode 6 and arranged in the longitudinal electrode gap region of the bottom conductive electrode 2 (e.g., Figure 2 As shown), or arranged above the bottom conductive electrode 2 (as shown). Figure 7 As shown, the force-sensitive sensing unit 3 is uniformly distributed in an alternating matrix pattern. Simultaneously, the temperature-sensitive sensing unit 5 is insulated from the bottom conductive electrode 2 by an insulating separator 4. The temperature-sensitive sensing unit 5 is positioned in the longitudinal electrode gap region of the bottom conductive electrode 2, or above the bottom conductive electrode 2, to avoid direct contact with the bottom conductive electrode 2 and thus prevent temperature signal interference. Each temperature-sensitive sensing unit constitutes an independent temperature detection node, and their arrayed deployment enables simultaneous temperature acquisition across multiple areas of the battery pack.

[0040] Furthermore, the temperature-sensitive sensing unit adopts a temperature-sensitive composite material, which is prepared by combining a flexible polymer substrate with temperature-sensitive material particles. The substrate is selected from flexible polymers such as PDMS and PI. The temperature-sensitive material particles are preferably, but not limited to, one or more composite systems of carbon nanotubes, graphene or metal nanoparticles. The thickness of the temperature-sensitive sensing unit is controlled between 2-100μm.

[0041] The temperature-sensitive sensing unit 5 and the force-sensitive sensing unit 3 are both fabricated using a dual-process synergistic approach combining negative pressure liquid-phase infiltration assembly with transient gas-phase foaming molding. Within the temperature-sensitive and force-sensitive functional layers, a multi-level interconnected mesoporous nanoframework is simultaneously constructed, forming a multi-level interconnected flexible three-dimensional porous network structure of "nanopores-mesopores-macro gaps." This structure effectively alleviates the curing stress of the polymer substrate, suppresses the sheet aggregation and stacking defects of materials such as carbon nanotubes, graphene, and MXene, and constructs a continuous, uniform, and stable three-dimensional conductive network. While significantly improving the sensitivity and linearity of temperature-sensitive and force-sensitive responses, it also greatly enhances the bending compliance and gas permeability of the material system. This allows for stable adaptation to the harsh service environment of a power battery pack's sealed cavity, high-temperature cycling, and repeated bending, solving the problems of performance drift, attenuation, and signal distortion of traditional sensors from a microstructural perspective.

[0042] The temperature-sensitive sensing unit 5 and the force-sensitive sensing unit 3 are prepared through a dual-process synergistic fabrication process combining negative pressure liquid-phase infiltration assembly with transient gas-phase foaming molding, forming a "nanopore-mesopore" microstructure. The insulating separator 4 serves as the insulating medium between the temperature-sensitive sensing unit 5 and the force-sensitive sensing unit 3. Simultaneously, a hollowed-out region is constructed between the first and second-layer force-sensitive sensing units of the force-sensitive sensing unit 3, forming a macroscopic gap structure.

[0043] Furthermore, the dual-process synergistic preparation of negative pressure liquid phase permeation assembly technology combined with transient gas phase foaming molding technology specifically includes the following steps: S1: Screen printing of sensing materials: Thermosensitive composite material or pressure-sensitive composite material is formed by screen printing and regularly printed on the surface of bottom conductive electrode 2 and top conductive electrode 6.

[0044] S2: Negative Pressure Liquid Phase Infiltration Assembly: First, a negative pressure liquid phase infiltration assembly process is used. Under negative pressure, the conductive particles inside the temperature-sensitive composite material are driven to arrange themselves in an orderly manner along the liquid phase infiltration direction, breaking the disordered aggregation state of the material and initially forming interwoven and interconnected nano-conductive pathways. The pressure-sensitive composite material, through negative pressure infiltration, enables conductive materials such as graphene and MXene two-dimensional sheet materials to overlap and vertically connect in an orderly manner, constructing a high-density conductive network.

[0045] S3: Transient Gas Phase Foaming Molding: Through a transient gas phase foaming molding process, the temperature-sensitive composite material utilizes a trace amount of foaming agent to instantaneously generate gas and form microbubbles during isothermal curing. This creates a uniform, interconnected mesoporous structure of 50-200 nm within the material, forming a multi-level interconnected three-dimensional nanoskeleton, i.e., a multi-level interconnected mesoporous nanoskeleton. Similarly, the pressure-sensitive composite material also utilizes a trace amount of foaming agent to instantaneously generate gas and form microbubbles during isothermal curing. Within the elastic substrate, uniform mesoporous pores are formed, with the pores and conductive network nested together to form a composite microstructure of "elastic substrate - mesoporous pores - nano-conductive pathways," i.e., a multi-level interconnected mesoporous nanoskeleton.

[0046] Furthermore, the multi-level interconnected three-dimensional nanoframework structure made of temperature-sensitive composite material can eliminate internal curing defects and conductive blind spots, enabling the conductive network to exhibit a highly linear resistance response with temperature changes. The resistance changes approximately linearly within the temperature range of -40℃ to 120℃, and the resistance drift within the operating range is ≤2%, demonstrating excellent long-term stability. This allows for precise detection of abnormal local temperature changes in the battery pack, timely identification of safety hazards such as cell overheating, and ensures the accuracy and reliability of temperature monitoring. Simultaneously, the flexible buffer structure of the porous framework can resist the thermal expansion and contraction stress caused by temperature fluctuations, preventing problems such as cracking and detachment of the sensing layer.

[0047] Furthermore, the multi-level interconnected mesoporous nanoframework structure made of pressure-sensitive composite material possesses excellent elastic deformation capability and conductive response characteristics. Under no pressure, the mesopores isolate conductive particles, resulting in a high-resistivity substrate. When subjected to minute pressure loads, the porous framework rapidly compresses and deforms, instantly increasing the contact density of conductive particles and causing a linear gradient change in resistance, accurately capturing minute pressure surges caused by battery cell expansion. Simultaneously, the multi-level porous structure buffers the deformation stress from repeated pressure cycles, preventing filler compaction and permanent failure of the conductive network, significantly improving the sensor's pressure cycling stability.

[0048] Furthermore, the top conductive electrode 6 covers the upper surface of the secondary force-sensitive sensing unit 32, and works in conjunction with the bottom conductive electrode 2 to form a crisscrossing electrode array, providing conductive paths for the acquisition of both temperature and pressure signals. The top conductive electrode 6 is made of the same flexible conductor as the bottom conductive electrode 2 (silver-based electrode or MXene-based composite conductive electrode), containing no fewer than four conductive paths, each path being uniformly arranged laterally, with an electrode width of 0.1-10 mm, a spacing of 50-500 μm between adjacent lateral electrodes, and an electrode thickness of 1-36 μm.

[0049] In this design, the lateral pathway of the top conductive electrode 6 intersects with the longitudinal pathway of the bottom conductive electrode 2, with each intersection area corresponding to a set of biphase force-sensitive sensing units, forming an independent pressure detection node. The top conductive electrode 6 is tightly integrated with the secondary force-sensitive sensing unit 32 to ensure stable electrical signal transmission.

[0050] Furthermore, the electrode edge area of ​​the top conductive electrode 6 covers a local surface of the temperature-sensitive sensing unit 5, which serves to fix and protect it, but does not block the core sensing area, thus avoiding interference with temperature detection.

[0051] Furthermore, the top electrode leads and bottom electrode leads are staggered to avoid mutual signal interference and facilitate zoned connection with the signal acquisition module.

[0052] Furthermore, a surface encapsulation protective layer 7 covers the upper surface of the top conductive electrode 6. It is made of a flexible film with high temperature resistance, aging resistance, and high insulation. PI film or PET film can be selected, and the thickness is controlled between 10 and 50 μm.

[0053] To eliminate cross-interference of pressure signals with temperature detection, the surface encapsulation protective layer 7 adopts a differentiated structural design. The area corresponding to the temperature-sensitive sensing unit is perforated, with the perforation size matching the size of the temperature-sensitive unit. This allows the temperature-sensitive sensing unit to directly contact the internal environment of the battery pack, accurately capturing temperature changes and avoiding thermal response hysteresis and detection deviations caused by the encapsulation layer. The area corresponding to the biphase force-sensitive sensing unit employs a locally raised structure with a thickness of 10–250 μm. This structure further enhances pressure response sensitivity while isolating external impact loads, preventing high pressure from directly acting on the temperature-sensitive sensing unit and causing resistance interference, thus ensuring the independence and accuracy of temperature detection.

[0054] Meanwhile, the surface encapsulation protective layer can effectively block environmental media such as dust, water vapor, and electrolyte from corroding, protect the internal electrodes, functional layers and insulation structures, and improve the overall service life of the sensor. Its own flexible characteristics do not affect the overall bending performance of the component and can maintain the conformal fit with the curved surface of the battery pack.

[0055] Furthermore, such as Figure 2 and Figure 6 As shown, the surface encapsulation protective layer 7 is hollowed out in the area of ​​the temperature-sensitive sensing unit 3 to form a protective layer hollow area 701. The protective layer hollow area 701 exposes the top conductive electrode 6. However, the exposed top conductive electrode does not pose any safety hazards such as electric shock or fire. It only has the problem of signal baseline drift caused by long-term corrosion and environment.

[0056] Therefore, in one implementation, an ultra-thin thermally conductive protective coating 9 can be printed. The ultra-thin thermally conductive protective coating 9, with its excellent thermal conductivity, can seal and protect the exposed top conductive electrode in the hollow area without affecting heat conduction, thus preventing corrosion, aging, and other issues from occurring on the exposed top conductive electrode.

[0057] Furthermore, in other embodiments, optimization can be achieved through software filtering, reducing the area of ​​the cutout region, etc., thereby reducing the impact on the core temperature monitoring function of the sensor.

[0058] like Figure 8 As shown, the present invention also provides a monitoring system for an array-type flexible temperature and pressure integrated sensor, including the aforementioned array-type flexible temperature and pressure integrated sensor, a signal acquisition module, a signal processing module, a data storage module, an early warning module, and a power supply module. The modules are connected to each other via wires or wireless communication to achieve comprehensive and real-time monitoring of the power battery pack status.

[0059] The flexible array-type integrated temperature and pressure sensor, as the core detection component of the system, is fitted onto the surface or internal gaps of the power battery pack. Its array-distributed temperature-sensitive sensing units correspond one-to-one with the location of each battery cell, enabling precise temperature monitoring of each cell. The crisscrossing electrode array corresponds to the pressure detection units, covering the entire surface and gap areas of the battery pack, achieving large-area, full-coverage pressure monitoring and ensuring no blind spots. The insulating separator within the sensor uses a perforated design to ensure the contact response sensitivity of the dual-phase force-sensitive sensing units, further improving the accuracy of pressure detection.

[0060] The signal acquisition module is electrically connected to the bottom and top conductive electrodes of the sensor, and is used to acquire in real time the resistance change signal (corresponding to the temperature signal) of the temperature-sensitive sensing unit and the resistance change signal (corresponding to the pressure signal) of the force-sensitive sensing unit corresponding to the crisscrossing electrode array. The signal acquisition frequency can be flexibly adjusted according to monitoring needs, with an adjustment range of 1-500Hz, which can ensure rapid capture of instantaneous changes in temperature and pressure, while avoiding increased power consumption caused by excessively high acquisition frequencies.

[0061] Furthermore, the signal acquisition module uses a high-precision analog-to-digital converter chip (such as ADS1256), which features low noise and high resolution. It can effectively filter out external interference signals, ensuring that the acquired resistance signal is true and accurate, and providing a reliable foundation for subsequent signal processing.

[0062] The signal processing module receives the resistance change signal transmitted by the signal acquisition module, performs a series of processing such as filtering, amplification, and analog-to-digital conversion on the signal, and converts the resistance change signal into identifiable and analyzable temperature and pressure data.

[0063] The specific processing procedure is as follows: First, temperature data conversion: by using a preset resistance-temperature calibration curve for the temperature-sensitive sensing unit, the resistance change signal of the temperature-sensitive sensing unit is converted into the corresponding temperature value, which can accurately obtain the temperature of the battery pack point corresponding to each temperature-sensitive sensing unit and realize the visualization of temperature distribution.

[0064] Secondly, pressure data conversion: by using the preset resistance-pressure calibration curve of the dual-phase force-sensitive sensing unit, combined with the position information of the crisscrossing electrode array, the resistance change signal of the pressure detection unit is converted into the corresponding pressure value, so as to realize the accurate presentation of the pressure distribution of the battery pack.

[0065] Thirdly, puncture risk identification is achieved by analyzing the abrupt changes in pressure signals and combining them with abnormal changes in temperature signals to accurately determine puncture risk. When a puncture occurs, the pressure detection unit at the puncture point will experience a sudden surge in pressure (a sharp change in resistance). At the same time, this is accompanied by an abnormal increase in local temperature (a sudden change in the resistance of the temperature-sensitive sensing unit). The signal processing module captures these dual characteristics to quickly determine the puncture risk, avoiding missed or false diagnoses.

[0066] The data storage module stores temperature and pressure data output by the signal processing module for at least one year and supports data backtracking and querying. It utilizes high-capacity, high-stability storage media (such as SD cards and solid-state drives), is vibration-resistant and resistant to high and low temperatures, and is compatible with the working environment of the power battery pack. This provides comprehensive data support for battery pack fault analysis, lifespan assessment, and safety traceability.

[0067] The warning module is electrically connected to the signal processing module and has preset temperature thresholds, pressure thresholds, and puncture judgment thresholds (which can be flexibly adjusted according to the needs of different battery pack specifications). When the monitored temperature exceeds the preset temperature threshold, the pressure exceeds the preset pressure threshold, or the signal processing module identifies a puncture risk, the warning module immediately issues a warning signal (e.g., sound level ≥ 80dB, flashing red light) and simultaneously transmits the warning information to the electric vehicle's central control system via wireless communication to remind the driver to take timely action. If necessary, it can trigger the battery pack protection mechanism to prevent safety accidents.

[0068] The power supply module provides a stable power supply for the entire monitoring system. It can utilize the power supply system of the battery pack itself or be equipped with a separate small lithium battery. The power supply module features a low-power mode, which automatically reduces system power consumption and extends system life when there are no abnormal signals from the sensors and the monitoring data is within the normal range. It also has overvoltage and overcurrent protection functions to ensure long-term stable operation of the system and meet the long-term working requirements of the battery pack.

[0069] This invention also provides a method for fabricating an array-type flexible temperature and pressure integrated sensor, comprising the following steps: S1. Preparation of flexible bearing substrate 1: Flexible insulating materials such as PDMS, PI, or PU are selected and prepared on the glass substrate by spin coating. The spin coating speed is 3000 r / min, the spin coating time is 30s-45s, and the thickness is 10μm-200μm. After curing at 80℃ for 1h, it is peeled off from the glass substrate to obtain a flexible bearing substrate with a smooth surface and excellent flexibility, which is extremely suitable for the complex curved surface bonding conditions of battery packs.

[0070] S2. Fabrication of the bottom conductive electrode 2: A silver-based electrode or an MXene-based composite conductive electrode is selected as the bottom conductive electrode material. It is printed onto the upper surface of the flexible substrate 1 using screen printing or formed onto the upper surface of the flexible substrate 1 using vacuum evaporation. At least four longitudinal conductive paths are provided, with an electrode width of 0.5mm-10mm, a spacing of 50μm-500μm between adjacent longitudinal electrodes, and an electrode thickness of 1μm-36μm. After printing, the electrode is cured at 100℃ to obtain the bottom conductive electrode. The electrode is thin and lightweight with no redundancy, and a contact resistance ≤5Ω, making it suitable for ultra-thin sensor structures. The electrode leads are fixed with conductive copper foil for easy connection to the signal acquisition module.

[0071] S3. Preparation of Insulating Separator 4: A liquid insulating epoxy adhesive with a thickness of 5μm-200μm is selected as the insulating separator material. After curing, this material has high insulation, excellent flexibility, and bonding stability, making it suitable for the repeated bending conditions of flexible sensors. Based on the size, position, and distribution of the biphasic force-sensitive sensing unit 3, precise cutout coating is performed using a mask-based point-forming process. The pre-cutout size is 0.4mm×0.4mm-5mm×5mm, corresponding one-to-one with the subsequent biphasic force-sensitive sensing units. After coating, it is pre-cured at low temperature for later use to achieve precise isolation and alignment of the two layers of force-sensitive sensing units.

[0072] S4. Preparation of the first-layer force-sensitive sensing unit 31: The first-layer force-sensitive sensing unit 31 uses flexible elastic materials such as PDMS elastomer or PU elastomer as the base material, adds 6%-8% graphene or MXene as pressure-sensitive material particles, and adds an appropriate amount of dispersant. After mixing evenly, it is ultrasonically dispersed for 20-30 minutes to obtain the first-layer pressure-sensitive composite material. Subsequently, the first-layer pressure-sensitive composite material is printed on the surface of the bottom conductive electrode 2 by screen printing, with a thickness of 2μm-100μm. After being cured at 100℃, an array-type force-sensitive sensing unit is formed. Finally, by combining negative pressure liquid phase infiltration assembly technology with transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm-200nm is constructed to form a uniform and interconnected flexible three-dimensional conductive porous structure.

[0073] S5. Fabrication of the second-layer force-sensitive sensing unit 32: The fabrication process is consistent with that of the first-layer force-sensitive sensing unit. Corresponding to the size, position and distribution of the first-layer force-sensitive sensing unit 31, it is printed on the surface of the top conductive electrode 6 by screen printing. A multi-level interconnected mesoporous nanoframework is constructed by combining negative pressure liquid phase infiltration assembly technology with transient gas phase foaming molding technology.

[0074] S6. Preparation of the temperature-sensitive sensing unit 5: Using flexible polymers such as PDMS or PI as the base material, 5wt%-6wt% of one or more composite systems of carbon nanotubes, graphene, or metal nanoparticles are added as temperature-sensitive conductive particles. An appropriate amount of dispersant is added, and after uniform mixing, the mixture is ultrasonically dispersed for 20-30 minutes to obtain a temperature-sensitive composite material. Subsequently, the temperature-sensitive composite material is screen-printed onto the surface of the top conductive electrode 6, and the second-layer force-sensitive sensing unit 32 is evenly distributed on the surface of the top conductive electrode 6 in an alternating lattice pattern. After printing, it is cured at 100℃ to form an array of temperature-sensitive sensing units. Each unit has a size of 0.4mm×0.4mm-5mm×5mm and a thickness of 2μm-100μm. Finally, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm-200nm is constructed inside the unit using negative pressure liquid-phase infiltration assembly technology combined with transient gas-phase foaming molding process.

[0075] S7. Fabrication of the top conductive electrode 6: The fabrication process is the same as that of the bottom conductive electrode. It is screen-printed onto the upper surface of the secondary force-sensitive sensing unit 32 and the temperature-sensitive sensing unit 5, with at least four lateral conductive paths. The electrode width is 0.5mm-10mm, the spacing between adjacent longitudinal electrodes is 50μm-500μm, and the electrode thickness is 1μm-36μm. These electrodes correspond one-to-one with the longitudinal electrodes of the bottom conductive electrode. After printing, the electrode leads are fixed with conductive copper foil to ensure tight contact with the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit, with a contact resistance ≤5Ω.

[0076] Furthermore, the pre-cured liquid insulating epoxy adhesive is used to separate the medium, ensuring that its hollowed-out area is precisely aligned and bonded to the first-layer force-sensitive sensing unit, and then adhered to the upper surface of the flexible support substrate. Strict adherence is maintained to ensure complete alignment between the hollowed-out area and the first-layer force-sensitive sensing unit, with no misalignment or obstruction.

[0077] Furthermore, to ensure that the secondary force-sensitive sensing unit 32 and the primary force-sensitive sensing unit 31 are aligned vertically in the hollowed-out area of ​​the insulating separator, the secondary force-sensitive sensing unit 32 is tightly bonded to the upper surface of the insulating separator, and then cured at a constant temperature of 120°C for 30 minutes to finally allow the liquid insulating epoxy adhesive to fully cure, forming a biphase force-sensitive sensing unit with a multi-level interconnected mesoporous nanoframework.

[0078] S8. Preparation of the surface encapsulation protective layer 7: A PI film or PET film with a thickness of 10μm-50μm is selected as the surface encapsulation protective layer material. A cutout is made in the area corresponding to each temperature-sensitive sensing unit 5, with the cutout size ≤ the size of the temperature-sensitive sensing unit. For the area corresponding to each biphasic force-sensitive sensing unit, a PI film is stacked and raised, with a raising thickness of 10μm-250μm. Subsequently, the surface encapsulation protective layer 7 is covered on the upper surface of the top conductive electrode 6 using a bonding process with double-sided adhesive or other adhesive products, and is then bonded and fixed to the flexible support substrate 1, ensuring a tight bond without bubbles or wrinkles, thus completing the overall fabrication of the sensor.

[0079] The order of preparation in steps S5-S7 is not limited. Alternatively, the secondary force-sensitive unit 32 and the temperature-sensitive unit 5 can be prepared first on the surface of the release material, followed by the preparation of the top conductive electrode 6 on the upper surface of the secondary force-sensitive unit and the temperature-sensitive unit. Or, the top conductive electrode 6 can be prepared first on the surface of the release material, followed by the preparation of the secondary force-sensitive unit 32 and the temperature-sensitive unit 5 on the upper surface of the top conductive electrode 6. Then, the completed release material unit is adhered to the upper end of the insulating separator 4, ensuring that the secondary force-sensitive unit 32 and the primary force-sensitive unit 31 are vertically aligned in the hollowed-out area of ​​the insulating separator. Finally, the release material is removed, realizing the transfer of the top conductive electrode.

[0080] Alternatively, a secondary force-sensitive sensing unit 32 and a temperature-sensitive sensing unit 5 can be directly fabricated on the upper end of the insulating separating medium, and a top conductive electrode 6 can be fabricated on the upper surface of the secondary force-sensitive sensing unit 32 and the temperature-sensitive sensing unit 5.

[0081] To better understand the technical solution of the present invention, please refer to the following embodiments: Example 1: As Figures 2-5 As shown.

[0082] I. Array-type flexible integrated temperature and pressure sensor: 1. Flexible bearing substrate: PDMS material with a thickness of 10μm is selected as the flexible bearing substrate.

[0083] 2. Bottom conductive electrode: Set on the surface of the flexible support substrate, with 6 longitudinal conductive paths, electrode width of 0.5mm, spacing between adjacent longitudinal electrodes of 50μm-100μm, and electrode thickness of 2μm.

[0084] 3. Insulating separation medium: The cutout size of the hollow area is 0.4mm×0.4mm, and the thickness is 6μm.

[0085] 4. First-layer force-sensitive sensing unit: It is arranged in a dot matrix pattern on the surface of the bottom conductive electrode, with a size of 0.4mm × 0.4mm and a thickness of 10μm. Through the synergistic process of negative pressure liquid phase infiltration assembly technology and transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm is constructed.

[0086] 5. Second-layer force-sensitive sensing unit: Corresponding to the position, distribution, and size of the first-layer force-sensitive sensing unit, it is set on the surface of the top conductive electrode, ensuring that it is vertically aligned with the first-layer force-sensitive sensing unit in the hollowed-out area of ​​the insulating separator. Its thickness is 10μm. A multi-level interconnected mesoporous nanoframework with a pore size of 50nm is constructed through a dual-process synergy of negative pressure liquid-phase infiltration assembly technology and transient gas-phase foaming molding.

[0087] 6. Temperature-sensitive sensing unit: Interleaved with the secondary force-sensitive sensing unit in a dot matrix on the surface of the top conductive electrode, with dimensions of 0.4mm × 0.4mm and a thickness of 10μm. A multi-level interconnected mesoporous nanoframework with a pore size of 50nm is constructed through a dual-process synergy of negative pressure liquid-phase infiltration assembly technology and transient gas-phase foaming molding process.

[0088] 7. Top conductive electrode: Located on the upper surface of the secondary force-sensitive sensing unit and temperature-sensitive sensing unit, with 6 transverse conductive paths. The electrode width is 0.5mm, the spacing between adjacent transverse electrodes is 50μm-100μm, and the electrode thickness is 2μm. It corresponds one-to-one with the longitudinal electrodes of the bottom conductive electrode. The first-layer force-sensitive sensing unit and the secondary force-sensitive sensing unit are located in the intersection area of ​​the bottom conductive electrode and the top conductive electrode.

[0089] Furthermore, the top conductive electrode, which is equipped with the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit, is fixedly positioned above the bottom conductive electrode through an insulating separating medium, ensuring that the secondary force-sensitive sensing unit and the primary force-sensitive sensing unit are vertically aligned in the hollowed-out area of ​​the insulating separating medium to form a dual-phase force-sensitive sensing unit.

[0090] 8. Surface Encapsulation Protective Layer: A 10μm thick PI film is selected as the surface encapsulation protective layer material. For each temperature-sensitive sensing unit area, a cutout is made with a cutout size of 0.4mm × 0.4mm. For each biphasic force-sensitive sensing unit area, a PI film is stacked and raised to a thickness of 20μm. The surface encapsulation protective layer is adhered and fixed to the upper surface of the top conductive electrode.

[0091] II. Monitoring System Components of the Array-Type Flexible Temperature and Pressure Integrated Sensor: 1. System Composition: It includes the flexible array-type temperature and pressure integrated sensor prepared in Example 1, a signal acquisition module (using ADS1256 analog-to-digital converter chip), a signal processing module (using STM32F407 microcontroller), a data storage module (using 32GB SD card), an early warning module (using audible and visual alarm, sound level 85dB, red flashing light), and a power supply module (using 3.7V small lithium battery).

[0092] 2. Installation and Connection: The sensor is attached to the surface of the power battery pack (ternary lithium battery pack, capacity 100Ah), so that the temperature-sensitive sensing unit corresponds to each cell position, and the crisscrossing electrode array covers the entire surface of the battery pack.

[0093] The signal acquisition module is connected to the bottom and top conductive electrodes of the sensor via wires. The signal processing module is electrically connected to the signal acquisition module, data storage module, and early warning module, respectively. The power supply module provides a stable 3.3V power supply to each module.

[0094] 3. Operating parameter settings: The signal acquisition frequency is set to 5Hz; the preset temperature threshold is 60℃ (exceeding this threshold indicates a temperature anomaly), and the pressure threshold is 5MPa (exceeding this threshold indicates a pressure anomaly).

[0095] 4. System workflow: (1) Signal acquisition: The signal acquisition module acquires the resistance change signal of the temperature sensing unit and the resistance change signal of the pressure detection unit in real time, filters out external interference signals, and transmits them to the signal processing module.

[0096] (2) Signal processing: The signal processing module filters, amplifies and converts the collected signals into digital signals. It calculates the temperature of each cell through the resistance-temperature calibration curve and the pressure value of each area of ​​the battery pack through the resistance-pressure calibration curve. It draws temperature and pressure distribution cloud maps. At the same time, it monitors the instantaneous changes in pressure and temperature. When the puncture judgment threshold is met, it is judged as a puncture risk.

[0097] (3) Data storage: The data storage module stores temperature data, pressure data and early warning records (abnormal temperature, abnormal pressure, puncture risk) to the SD card for 2 years and supports data backtracking query.

[0098] (4) Warning trigger: When the temperature exceeds 60℃ and the pressure exceeds 5MPa, the warning module immediately issues an audible and visual warning and transmits the warning information to the electric vehicle central control system to remind the driver to stop and check in time to avoid safety accidents.

[0099] The performance of the sensor in Example 1 was tested, such as... Figure 9 and Figure 10 As shown, the test results are as follows: (1) Temperature detection performance: In the range of -40℃ to 120℃, the resistance of the temperature sensing unit changes linearly, the resistance drift is ≤2%, and the temperature measurement error is ≤±1℃, which meets the requirements of power battery pack temperature monitoring. (2) Pressure detection performance: The pressure detection range is 0-10MPa. The pressure change and the resistance change have a good correspondence. The pressure measurement error is ≤±0.1MPa. After 5000 pressure cycle tests, the performance decay is ≤5%, and the resilience is excellent. The insulating separation medium effectively avoids signal interference, and the pressure detection stability is significantly improved.

[0100] (3) Flexibility: The sensor can be bent to a radius of curvature of 5mm. After 1000 bends, the resistance change is ≤3%, with no delamination or peeling. It can fit the curved surface of the battery pack. The liquid insulating epoxy adhesive has good flexibility after curing and does not affect the overall flexibility and bonding performance of the sensor.

[0101] (4) Anti-interference performance: Under pressure, the resistance change of the temperature-sensitive functional unit is ≤1%, with no obvious interference and excellent temperature detection stability; the dual-phase force-sensitive sensing unit has no signal crosstalk and stable detection accuracy.

[0102] Test results show that the monitoring system can monitor the temperature and pressure changes of the battery pack in real time and accurately, with a fast response speed (≤1s), timely and reliable early warning, and can effectively capture safety hazards such as cell overheating, cell expansion, and puncture, meeting the comprehensive safety monitoring needs of power battery packs.

[0103] Example 2: As Figure 7 As shown.

[0104] I. Array-type flexible integrated temperature and pressure sensor: 1. Flexible bearing substrate: PDMS material with a thickness of 100μm is selected as the flexible bearing substrate.

[0105] 2. Bottom conductive electrode: Set on the surface of the flexible support substrate, with 6 longitudinal conductive paths, electrode width of 5mm, spacing between adjacent longitudinal electrodes of 200μm-300μm, and electrode thickness of 18μm.

[0106] 3. Insulating separation medium: The cutout size of the hollow area is 5mm×5mm, and the thickness is 100μm.

[0107] 4. First-layer force-sensitive sensing unit: It is arranged in a dot matrix pattern on the surface of the bottom conductive electrode, with a size of 5mm×5mm and a thickness of 40μm. Through the synergistic process of negative pressure liquid phase infiltration assembly technology and transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 100nm is constructed.

[0108] 5. Second-layer force-sensitive sensing unit: Corresponding to the position, distribution, and size of the first-layer force-sensitive sensing unit, it is set on the surface of the top conductive electrode, ensuring that it is vertically aligned with the first-layer force-sensitive sensing unit in the hollowed-out area of ​​the insulating separator, with a thickness of 50μm. A multi-level interconnected mesoporous nanoframework with a pore size of 100nm is constructed through a dual-process synergy of negative pressure liquid-phase infiltration assembly technology and transient gas-phase foaming molding.

[0109] 6. Temperature-sensitive sensing unit: Interleaved with the secondary force-sensitive sensing unit in a dot matrix on the surface of the top conductive electrode, with dimensions of 5mm × 5mm and a thickness of 50μm. A multi-level interconnected mesoporous nanoframework with a pore size of 100nm is constructed through a dual-process synergy of negative pressure liquid-phase infiltration assembly technology and transient gas-phase foaming molding process.

[0110] 7. Top conductive electrode: Located on the upper surface of the secondary force-sensitive sensing unit and temperature-sensitive sensing unit, with 6 transverse conductive paths. The electrode width is 5mm, the spacing between adjacent transverse electrodes is 200μm-300μm, and the electrode thickness is 18μm. It crosses one-to-one with the longitudinal electrodes of the bottom conductive electrode. The first-layer force-sensitive sensing unit and the secondary force-sensitive sensing unit are located in the intersection area of ​​the bottom conductive electrode and the top conductive electrode.

[0111] Furthermore, the top conductive electrode, which is equipped with the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit, is fixedly positioned above the bottom conductive electrode through an insulating separating medium, ensuring that the secondary force-sensitive sensing unit and the primary force-sensitive sensing unit are vertically aligned in the hollowed-out area of ​​the insulating separating medium to form a dual-phase force-sensitive sensing unit.

[0112] 8. Surface Encapsulation Protective Layer: A 30μm thick PET film is selected as the surface encapsulation protective layer material. For each temperature-sensitive sensing unit area, a cutout is made; for each biphasic force-sensitive sensing unit area, a film is stacked and raised to a thickness of 100μm. The surface encapsulation protective layer is adhered and fixed to the upper surface of the top conductive electrode.

[0113] II. Monitoring System Components of the Array-Type Flexible Temperature and Pressure Integrated Sensor: The system hardware configuration is consistent with that of Example 1, including a high-precision signal acquisition module, a microcontroller processing module, a large-capacity storage module, an audible and visual warning module, and an independent power supply module. It is installed on the surface of a standard 100Ah ternary lithium battery pack, with a sampling frequency of 5Hz and consistent temperature and pressure thresholds. The system offers enhanced operational stability, superior structural deformation resistance compared to lower-parameter solutions, and balances flexibility and durability, making it suitable for long-term monitoring of the battery pack under normal operation, temperature fluctuations, and slight vibration conditions.

[0114] The performance of the sensor in Example 2 was tested, such as... Figure 9 and Figure 10 As shown, the test results are as follows: Temperature measurement error ≤ ±1℃, resistance drift ≤ 2%; pressure measurement error ≤ ±0.1MPa, 5000-cycle attenuation ≤ 5%; structural rigidity is better than Example 1, resistance to minor impact is improved, resistance change ≤ 2.5% after 1000 bends, no delamination or cracking, balanced overall performance, suitable for general monitoring scenarios of mass-produced power battery packs.

[0115] Example 2: As Figure 2 As shown.

[0116] I. Array-type flexible integrated temperature and pressure sensor: 1. Flexible bearing substrate: PI material with a thickness of 200μm is selected as the flexible bearing substrate.

[0117] 2. Bottom conductive electrode: It is set on the surface of the flexible support substrate, with 6 longitudinal conductive paths. The electrode width is 10mm, the spacing between adjacent longitudinal electrodes is 500μm, and the electrode thickness is 36μm.

[0118] 3. Insulating separation medium: The cutout size of the hollow area is 4mm×4mm, and the thickness is 200μm.

[0119] 4. First-layer force-sensitive sensing unit: It is arranged in a dot matrix pattern on the surface of the bottom conductive electrode, with a size of 4mm×4mm and a thickness of 80μm. Through the synergistic process of negative pressure liquid phase infiltration assembly technology and transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 200nm is constructed.

[0120] 5. Second-layer force-sensitive sensing unit: Corresponding to the position, distribution, and size of the first-layer force-sensitive sensing unit, it is set on the surface of the top conductive electrode, ensuring vertical alignment with the first-layer force-sensitive sensing unit in the hollowed-out area of ​​the insulating separator. Its thickness is 100μm. A multi-level interconnected mesoporous nanoframework with a pore size of 200nm is constructed through a dual-process synergy of negative pressure liquid-phase infiltration assembly technology and transient gas-phase foaming molding.

[0121] 6. Temperature-sensitive sensing unit: It is arranged in a lattice pattern with the secondary force-sensitive sensing unit on the surface of the top conductive electrode, with dimensions of 4mm × 4mm and a thickness of 100μm. Through the synergistic effect of negative pressure liquid phase infiltration assembly technology and transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 200nm is constructed.

[0122] 7. Top conductive electrode: It is set on the upper surface of the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit. It has 6 transverse conductive paths, the electrode width is 5mm, the spacing between adjacent transverse electrodes is 500μm, and the electrode thickness is 36μm. It crosses one by one with the longitudinal electrodes of the bottom conductive electrode. The first-layer force-sensitive sensing unit and the secondary force-sensitive sensing unit are set in the intersection area of ​​the bottom conductive electrode and the top conductive electrode.

[0123] Furthermore, the top conductive electrode, which is equipped with the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit, is fixedly positioned above the bottom conductive electrode through an insulating separating medium, ensuring that the secondary force-sensitive sensing unit and the primary force-sensitive sensing unit are vertically aligned in the hollowed-out area of ​​the insulating separating medium to form a dual-phase force-sensitive sensing unit.

[0124] 8. Surface Encapsulation Protective Layer: A 50μm thick PI film is selected as the surface encapsulation protective layer material. For each temperature-sensitive sensing unit area, a cutout is made; for each biphasic force-sensitive sensing unit area, a film is stacked and raised to a thickness of 250μm. The surface encapsulation protective layer is adhered and fixed to the upper surface of the top conductive electrode.

[0125] II. Monitoring System Components of the Array-Type Flexible Temperature and Pressure Integrated Sensor: The hardware configuration has been upgraded and optimized, featuring an ADS1256 high-precision acquisition chip, an STM32F407 processing module, a 32GB anti-vibration SD card, and an 85dB audible and visual warning module, making it compatible with power supply modules for harsh operating conditions. Installed inside a high-temperature, high-load power battery pack, it operates at a 5Hz acquisition frequency and can withstand alternating high and low temperatures and continuous vibration conditions. The signal acquisition is drift-free and distortion-free, accurately capturing temperature anomalies, minute pressure changes, and puncture risks under extreme conditions, and providing stronger data storage stability.

[0126] The performance of the sensor in Example 3 was tested, such as... Figure 9and Figure 10 As shown, the test results are as follows: Temperature detection error ≤ ±0.8℃, resistance drift ≤ 1.5% over a wide temperature range of -40℃ to 120℃; pressure detection error ≤ ±0.08MPa, significantly improved pressure sensitivity; highest structural strength, best resistance to impact, aging, and vibration, resistance change ≤ 2% after 1000 bends, performance decay ≤ 3% after 5000 pressure cycles, high adaptability to extreme environments, suitable for high-precision safety monitoring needs of high-end power battery packs and high-load operating conditions.

[0127] like Figure 9 and Figure 10 As shown, the pressure performance characteristic curves and temperature-sensitive performance characteristic curves of different embodiments and comparative examples are presented.

[0128] like Figure 9 The figures shown are pressure performance characteristic curves for different embodiments and comparative examples. From top to bottom, they are the characteristic curves for the comparative example (traditional single-layer sensor), Example 1, Example 2, and Example 3. As can be seen from the curves, the three embodiments of the present invention, relying on a multi-level interconnected mesoporous nanoframework + biphase force-sensitive sensing unit structure, exhibit significantly better pressure response linearity and low-pressure sensitivity than traditional single-layer sensors. Among them, Example 3 has the steepest curve slope, demonstrating the best ability to identify minute pressure signals, making it suitable for precise monitoring of minute expansion pressure in power battery pack cells.

[0129] like Figure 10 The figure shows the characteristic curves of the temperature-sensitive properties of different embodiments and comparative examples. Taking the right-hand point as the reference, from top to bottom, they are the characteristic curves of Embodiment 1, Embodiment 2, Embodiment 3, and the comparative example (B3950 10k ceramic NTC thermistor). NTC has a negative temperature coefficient, and its resistance decreases exponentially with increasing temperature.

[0130] As can be seen from the curves, the traditional B3950 10k ceramic NTC thermistor exhibits an exponential negative temperature response, with significant differences in sensitivity between high and low temperatures, making it only suitable for rigid single-point temperature measurement. The temperature-sensitive sensing unit in each embodiment of this invention uses a multi-level mesoporous framework structure of graphene-silver nanocomposite filler, exhibiting nonlinear PTC characteristics: in the low-temperature range, the polymer substrate exhibits weak thermal expansion, resulting in a slow and gradual increase in resistance; above 60°C, the substrate expands dramatically, the mesoporous pores expand, leading to a rapid reduction in conductive pathways and a significantly increased resistance growth slope. This characteristic allows for stable monitoring of normal temperatures within the normal operating range of the battery pack (20-60°C), and significantly improves temperature resolution sensitivity in the thermal runaway warning range (>60°C), enabling earlier identification of cell overheating risks. Furthermore, this invention can be fabricated flexibly over a large area, eliminating temperature measurement blind spots. The high-temperature response sensitivity of Examples 1-3 is excellent, making it suitable for high-temperature thermal runaway warning scenarios in power battery packs.

[0131] The secondary force-sensitive sensing unit is tightly bonded to the upper surface of the insulating separator and aligned vertically with the primary force-sensitive sensing unit through a perforated area in the insulating separator. It has a thickness of 10 μm and is cured at 120°C for 30 minutes, allowing the liquid insulating epoxy adhesive to fully cure. Simultaneously, the internal nanoframework is shaped, forming a biphase force-sensitive sensing unit with a multi-level interconnected mesoporous nanoframework.

[0132] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An array-type flexible integrated temperature and pressure sensor, characterized in that: include: The system comprises a flexible support substrate for mechanical support, a bottom conductive electrode disposed above the flexible support substrate, a force-sensitive functional matrix integrated on the upper surface of the bottom conductive electrode, an insulating separating medium covering the force-sensitive functional matrix, an upper force-sensitive response layer aligned vertically with the force-sensitive functional matrix, a top conductive electrode located at the upper end of the upper force-sensitive response layer, a temperature-sensitive functional matrix integrated on the lower surface of the top conductive electrode and uniformly distributed with the upper force-sensitive response layer on the lower surface of the top conductive electrode in an alternating lattice pattern, and a surface encapsulation protective layer for overall protection. The force-sensitive functional matrix and its upper force-sensitive response layer form an array of force-sensitive sensing units, and the temperature-sensitive functional matrix forms an array of temperature-sensitive sensing units. The force-sensitive sensing units and the temperature-sensitive sensing units are evenly distributed in an alternating lattice pattern between the top conductive electrode and the bottom conductive electrode to form a force-sensitive / temperature-sensitive composite functional matrix, which completely covers the surface of the flexible bearing substrate to achieve ultra-large area full-domain synchronous monitoring. The flexible support substrate, the bottom conductive electrode, the force-sensitive / temperature-sensitive composite functional matrix, the insulating separator, the top conductive electrode, and the surface encapsulation protective layer are then encapsulated in an integrated stacked structure from bottom to top.

2. The array-type flexible integrated temperature and pressure sensor according to claim 1, characterized in that: Both the force-sensitive sensing unit and the temperature-sensitive sensing unit are prepared using a dual-process synergistic approach combining negative pressure liquid-phase permeation assembly with transient gas-phase foaming molding. Inside the force-sensitive sensing unit and the temperature-sensitive sensing unit, a multi-level interconnected mesoporous nanoframework of 50nm-200nm is constructed, forming a multi-level interconnected flexible three-dimensional porous network structure.

3. The array-type flexible integrated temperature and pressure sensor according to claim 2, characterized in that: The temperature-sensitive sensing unit includes a temperature-sensitive composite material, which includes a flexible polymer and temperature-sensitive material particles. The flexible insulating polymer includes one or more composite systems of PDMS and PI, and the temperature-sensitive material particles include one or more composite systems of carbon nanotubes, graphene, and metal nanoparticles. The force-sensitive sensing unit includes a pressure-sensitive composite material, which includes an elastic substrate and pressure-sensitive material particles. The elastic substrate includes one or more compound systems of PDMS and PU, and the pressure-sensitive material particles include one or more compound systems of graphene and MXene.

4. The array-type flexible integrated temperature and pressure sensor according to claim 1, characterized in that: Both the bottom conductive electrode and the top conductive electrode are equipped with no less than four conductive paths, which are arranged in a longitudinal and transverse cross pattern to form a cross-shaped electrode array with n×m intersection points, providing conductive paths for the acquisition of pressure and temperature dual signals; the force-sensitive sensing unit is located at the intersection of the bottom conductive electrode and the top conductive electrode.

5. The array-type flexible integrated temperature and pressure sensor according to claim 1, characterized in that: The force-sensitive sensing unit includes a first-layer force-sensitive sensing unit and a second-layer force-sensitive sensing unit arranged vertically. The first-layer force-sensitive sensing unit is integrated on the upper surface of the bottom conductive electrode as the force-sensitive functional matrix; the second-layer force-sensitive sensing unit serves as the upper force-sensitive response layer and is integrated on the lower surface of the top conductive electrode. The insulating separating medium is disposed around the force-sensitive sensing unit and is tightly attached to the force-sensitive sensing unit, surrounding the first-layer force-sensitive sensing unit and the second-layer force-sensitive sensing unit in the force-sensitive sensing unit, forming a two-phase sensing structure with upper and lower alignment, thus constituting a two-phase force-sensitive sensing unit.

6. An array-type flexible integrated temperature and pressure sensor according to any one of claims 1-5, characterized in that: The surface encapsulation protective layer has a hollowed-out area corresponding to each temperature-sensitive sensing unit, with the hollowed-out size being less than or equal to the size of the temperature-sensitive sensing unit, forming a hollowed-out area of ​​the protective layer; the area corresponding to each force-sensitive sensing unit is raised by a thin film stacking process.

7. The array-type flexible integrated temperature and pressure sensor according to claim 6, characterized in that: An ultra-thin thermally conductive protective coating is printed within the hollowed-out area of ​​the protective layer.

8. A method for fabricating an array-type flexible integrated temperature and pressure sensor, characterized in that: Includes the following steps: S1: Preparation of flexible load-bearing substrate: Flexible insulating materials such as PDMS, PI, or PU are selected and prepared by spin coating to obtain a flexible load-bearing substrate; S2: Preparation of bottom conductive electrode: Select silver-based electrode or MXene-based composite conductive electrode as bottom conductive electrode material, print it on the upper surface of flexible support substrate by screen printing, or form it on the upper surface of flexible support substrate by vacuum evaporation process, arrange at least four longitudinal conductive paths, and obtain bottom conductive electrode after constant temperature curing. S3: Preparation of insulating separation medium: Liquid insulating epoxy adhesive is selected as the insulating separation medium material. According to the size, position and distribution of the force-sensitive sensing unit, precise hollow coating is carried out. The mask plate fixed point forming process is adopted, and the hollow size is reserved. After the coating is completed, it is pre-cured at low temperature for later use. S4. Preparation of the first-layer force-sensitive sensing unit: Using PDMS elastomer or PU elastomer as the base material, add 6%-8% graphene or MXene as pressure-sensitive material particles, and add an appropriate amount of dispersant. After mixing evenly, ultrasonically disperse to obtain the first-layer pressure-sensitive composite material. Subsequently, the first-layer pressure-sensitive composite material is printed on the surface of the bottom conductive electrode by screen printing. After isothermal curing, an array-type force-sensitive sensing unit is formed. Finally, through the synergistic process of negative pressure liquid phase infiltration assembly technology combined with transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm-200nm is constructed to form a uniform and interconnected flexible three-dimensional conductive porous structure. S5. Preparation of secondary force-sensitive sensing units: The preparation process is consistent with that of the first-layer force-sensitive sensing unit. Corresponding to the size, position and distribution of the first-layer force-sensitive sensing unit, the second-layer force-sensitive sensing unit is printed on the surface of the top conductive electrode by screen printing. The second-layer force-sensitive sensing unit is constructed by combining the negative pressure liquid phase infiltration assembly technology with the transient gas phase foaming molding process. S6. Preparation of temperature-sensitive sensing unit: Using flexible polymers such as PDMS or PI as the base material, add 5wt%-6wt% of one or more composite systems of carbon nanotubes, graphene or metal nanoparticles as temperature-sensitive conductive particles, and add an appropriate amount of dispersant. After mixing evenly, ultrasonically disperse to obtain temperature-sensitive composite material. Subsequently, the temperature-sensitive composite material is printed on the surface of the top conductive electrode by screen printing. It is evenly distributed on the surface of the top conductive electrode in an alternating lattice with the secondary force-sensitive sensing unit. After printing, it is cured at a constant temperature to form an array-type temperature-sensitive sensing unit. Finally, by combining negative pressure liquid phase infiltration assembly technology with transient gas phase foaming molding process, a multi-level interconnected mesoporous nanoframework with a pore size of 50nm-200nm is constructed inside the unit. S7. Preparation of top conductive electrode: The preparation process is the same as that of bottom conductive electrode. At least four transverse conductive paths are prepared on the upper surface of the secondary force-sensitive sensing unit and temperature-sensitive sensing unit by screen printing, and they are cross-corresponding to the longitudinal electrodes of the bottom conductive electrode. After printing, the electrode leads are fixed by conductive copper foil to ensure close contact with the secondary force-sensitive sensing unit and temperature-sensitive sensing unit, with a contact resistance ≤5Ω. S8: Assembly: The pre-cured liquid insulating epoxy adhesive is separated into media, ensuring that its hollowed-out area is precisely aligned and bonded to the first-layer force-sensitive sensing unit, and then bonded to the upper surface of the flexible bearing substrate. Strictly ensure that the hollowed-out area is completely aligned with the first-layer force-sensitive sensing unit, without any offset or obstruction; then, ensure that the second-layer force-sensitive sensing unit is aligned vertically with the first-layer force-sensitive sensing unit in the hollowed-out area of ​​the insulating separator. After tightly bonding the second-layer force-sensitive sensing unit to the upper surface of the insulating separator, and then curing at a constant temperature, the liquid insulating epoxy adhesive is completely cured to form a biphase force-sensitive sensing unit with a multi-level interconnected mesoporous nanoframework. S9. Preparation of surface encapsulation protective layer: Select PI film or PET film as the surface encapsulation protective layer material, and cut out the area corresponding to each temperature-sensitive sensing unit. The cutout size is ≤ the size of the temperature-sensitive sensing unit. The area corresponding to each biphase force-sensitive sensing unit is raised by film stacking. Subsequently, the surface encapsulation protective layer is covered on the top conductive electrode through the bonding process of adhesive products, and then bonded and fixed to the flexible support substrate to ensure tight bonding without bubbles or wrinkles, thus completing the overall fabrication of the sensor. Steps S5-S7 are fabricated sequentially. First, a secondary force-sensitive sensing unit and a temperature-sensitive sensing unit are fabricated on the surface of the release material. Then, a top conductive electrode is fabricated on the upper surface of the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit. Alternatively, a top conductive electrode is fabricated on the surface of the release material first. Then, a secondary force-sensitive sensing unit and a temperature-sensitive sensing unit are fabricated on the upper surface of the top conductive electrode. Subsequently, the completed release material unit is bonded to the upper end of the insulating separator medium, ensuring that the secondary force-sensitive sensor unit and the primary force-sensitive sensor unit are aligned vertically in the hollowed-out area of ​​the insulating separator medium; finally, the release material is removed to transfer the top conductive electrode. Alternatively, a secondary force-sensitive sensing unit and a temperature-sensitive sensing unit can be directly fabricated on the upper end of the insulating separating medium, and a top conductive electrode can be fabricated on the upper surface of the secondary force-sensitive sensing unit and the temperature-sensitive sensing unit.

9. The method for fabricating an array-type flexible temperature and pressure integrated sensor according to claim 8, characterized in that: The negative pressure liquid phase permeation assembly technology, combined with transient gas phase foaming molding process, includes the following steps: S11: Screen printing of sensing materials: Thermosensitive composite materials or pressure-sensitive composite materials are regularly printed on the surface of the bottom conductive electrode or the top conductive electrode in an interlaced matrix pattern using a screen. S12: Negative pressure liquid phase infiltration assembly: First, a negative pressure liquid phase infiltration assembly process is adopted. Under negative pressure, the conductive particles inside the temperature-sensitive composite material are driven to arrange themselves in an orderly manner along the liquid phase infiltration direction, breaking the disordered agglomeration state of the material and initially forming an interwoven and interconnected nano-conductive pathway; the pressure-sensitive composite material enables the conductive materials of graphene and MXene two-dimensional sheet materials to overlap and vertically connect in an orderly manner through negative pressure infiltration, constructing a high-density conductive network; S13: Transient vapor phase foaming molding: Through the transient vapor phase foaming molding process, the temperature-sensitive composite material utilizes a small amount of foaming agent to generate gas instantaneously and form microbubbles during the isothermal curing process, generating a mesoporous structure with uniform pore size and interconnection inside the material, forming a multi-level interconnected mesoporous nanoskeleton; the pressure-sensitive composite material also uses a small amount of foaming agent to generate gas instantaneously and form microbubbles during the isothermal curing process, forming uniform mesoporous pores inside the elastic substrate, with the pores and conductive network nested together to form a multi-level interconnected mesoporous nanoskeleton.

10. A monitoring system for an array-type flexible integrated temperature and pressure sensor, characterized in that: The system includes the array-type flexible temperature and pressure integrated sensor, signal acquisition module, signal processing module, data storage module, early warning module, and power supply module as described in claim 1. The modules are connected to each other via wires or wireless communication to achieve comprehensive and real-time monitoring of the power battery pack status. The array-type flexible temperature and pressure integrated sensor, as the core monitoring component of the system, is fitted and installed on the surface or inside the gap of the power battery pack. The signal acquisition module is connected to the bottom conductive electrode and the top conductive electrode of the sensor, and is used to acquire the resistance change signal of the temperature-sensitive sensing unit and the resistance change signal of the force-sensitive sensing unit in real time. The signal processing module receives the resistance change signal transmitted by the signal acquisition module, performs filtering, amplification, and analog-to-digital conversion on the signal, converts the resistance change signal into identifiable and analyzable temperature and pressure data, and identifies the puncture risk based on the abrupt change characteristics of the pressure and temperature data. The data storage module is used to store the temperature and pressure data output by the signal processing module; The early warning module is electrically connected to the signal processing module. The system presets a temperature threshold, a pressure threshold, and a puncture judgment threshold. When the monitored data exceeds the judgment threshold, the early warning module issues an early warning signal. The power supply module provides a stable power supply for the entire monitoring system.

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