A discharge-enhanced high-efficiency mechanical energy collection device and collection method

Abstract

The present invention belongs to the field of mechanical energy collection technology, and relates to a discharge-enhanced high-efficiency mechanical energy collection device and collection method. The collection device includes a first electrode, a second electrode, and a dielectric layer located between the two; the number of dielectric layers is one and is connected to the first electrode, and the dielectric layer and the second electrode have the characteristic of inducing electrostatic breakdown due to charge accumulation under mechanical force; or, the number of dielectric layers is two, respectively connected to the first electrode and the second electrode, and the two dielectric layers have the characteristic of inducing electrostatic breakdown due to charge accumulation under mechanical force; each dielectric layer is provided with a channel for the discharge current generated by electrostatic breakdown to pass through, and then collected by the first electrode and the second electrode. The collection method is to apply a mechanical force to the collection device, induce electrostatic breakdown to generate a discharge current, and then collect the discharge current by the first electrode and the second electrode. The present invention can increase current density, reduce internal resistance, and improve energy conversion efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical energy collection, and relates to a discharge-enhanced high-efficiency mechanical energy collection device and a collection method. Background Art

[0002] Electrostatic breakdown occurs in a high electric field strength environment. When the electric field strength reaches or exceeds a certain threshold (for example, the breakdown threshold of air is about 3×10 6 When the electric field is applied to the dielectric or air (at a specific voltage of 1 V / m), the molecules and atoms in the dielectric or air are forcibly stripped of their electrons by the electric field, resulting in ionization. This ionization process transforms the originally insulating dielectric or air into a conductive medium, allowing the rapid release of charge energy.

[0003] Driven by the demand for sustainable energy development, mechanical energy harvesting devices, as key equipment for converting environmental mechanical energy into electrical energy, are widely used in self-powered systems such as wearable devices, medical implants and industrial sensors. In the early days, electrostatic breakdown was considered a harmful factor in the operation of mechanical energy harvesting devices. This unexpected rapid release of energy will significantly reduce the charge density of the system and seriously affect the energy output efficiency of the electrostatic induction process. In the actual design and application of mechanical energy harvesting devices, people have taken various measures to avoid the negative impact of electrostatic breakdown. For example, the patent with authorization announcement number CN109474199B aims to avoid the occurrence of air breakdown by setting a self-voltage doubling rectifier circuit and a voltage regulation circuit composed of diodes and capacitors.

[0004] As research deepened, researchers gradually realized the energy utilization potential of electrostatic breakdown and began to explore technical paths to apply it to mechanical energy harvesting. For example, the patent application with publication number CN118573046A discloses a DC triboelectric nanogenerator based on triboelectric charging and electrostatic breakdown. It attempts to utilize the discharge current generated by electrostatic breakdown, but actually only collects the induced current, resulting in a single device collecting current of less than 1μA and a transferred charge of less than 150nC. For another example, the patent application with publication number CN111510016A discloses a DC nanogenerator that can simultaneously harvest mechanical energy and thermal energy. However, its energy harvesting mechanism still relies on the displacement current generated by electrostatic induction to form a closed loop. The high impedance power supply internal resistance introduced by the insulating medium seriously restricts the energy output performance, making the collected current less than 1.1μA.

[0005] In the field of mechanical energy harvesting, existing technologies utilizing electrostatic breakdown still face numerous technical bottlenecks, primarily manifested in low output current density (<10μA / cm²), high internal resistance (MΩ-GΩ), and low energy conversion efficiency. Effectively utilizing electrostatic breakdown to overcome the performance shortcomings of existing technologies and develop new, highly efficient mechanical energy harvesting devices based on electrostatic breakdown has become a key research direction in this field. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems existing in the prior art and to provide a discharge-enhanced high-efficiency mechanical energy collection device and collection method.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A discharge-enhanced high-efficiency mechanical energy harvesting device comprises a first electrode, a second electrode and a dielectric layer located therebetween;

[0009] The number of the dielectric layer is one, denoted as dielectric layer a, the dielectric layer a is connected to the first electrode, and the dielectric layer a and the second electrode have the characteristic of inducing electrostatic breakdown due to charge accumulation under mechanical force;

[0010] Alternatively, the number of dielectric layers is two, denoted as dielectric layer b and dielectric layer c, dielectric layer b is connected to the first electrode, dielectric layer c is connected to the second electrode, and dielectric layer b and dielectric layer c have the characteristic of inducing electrostatic breakdown due to charge accumulation under mechanical force;

[0011] Each dielectric layer is provided with a channel for the discharge current generated by electrostatic breakdown to pass through and then be collected by the first electrode and the second electrode.

[0012] By providing channels in the dielectric layer (serving as low-resistance conductive pathways with an internal resistance of approximately 15Ω), the present invention allows the discharge current generated by electrostatic breakdown to be directly transported to electrodes for collection (conduction current), eliminating the need for the traditional, slow electrostatic induction process (displacement current). This allows reversible impedance switching to be achieved through electrode-to-electrode discharge. During the force-to-electricity conversion process initiated by mechanical forces (such as contact, separation, and sliding), the dielectric layer maintains insulation and stores charge. Voltage accumulation triggers plasma discharge, and during the electrostatic energy release process, the dielectric layer exhibits the high conductivity of plasma, efficiently releasing energy, increasing the overall circuit current and the energy contribution of electrical consumers. Consequently, the mechanical energy harvesting device boasts high maximum energy conversion efficiency, high current flow, and low impedance.

[0013] As the preferred technical solution:

[0014] A discharge-enhanced high-efficiency mechanical energy harvesting device as described above, wherein when the number of dielectric layers is one, the thickness of dielectric layer a is not less than 50 μm, and is suitable for accumulating voltage to an air breakdown threshold;

[0015] When the number of dielectric layers is two, the sum of the thicknesses of dielectric layer b and dielectric layer c is not less than 50 μm, which is suitable for accumulating voltage to the air breakdown threshold;

[0016] The thickness of the first electrode or the second electrode is 1 μm-10 cm;

[0017] The shapes of the first electrode, the second electrode, and each dielectric layer can be set arbitrarily. All three are arranged horizontally, and the vertical projection area is greater than or equal to 1 cm² to support electrostatic breakdown between electrodes.

[0018] In the discharge-enhanced high-efficiency mechanical energy harvesting device described above, the porosity of each dielectric layer is 60-90% and the pore size is 0.2-7 μm. The porosity and average pore size are set in this way, which can not only ensure that the effective contact area of ​​each dielectric layer is large, so that more charge can be accumulated under mechanical force, but also ensure that the discharge current generated by electrostatic breakdown can pass through the dielectric layer.

[0019] As described above, in a discharge-enhanced high-efficiency mechanical energy harvesting device, the material of each dielectric layer is a polymer, metal oxide, carbon-based material or composite material, and the relative dielectric constant of each dielectric layer is greater than 2, which is conducive to storing higher charges, thereby increasing the current of each discharge.

[0020] In a discharge-enhanced high-efficiency mechanical energy harvesting device as described above, the materials of the first electrode and the second electrode are independently selected from one of copper (Cu), aluminum (Al), gold (Au), silver (Ag), graphene, carbon nanotubes (CNT), poly (3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPy), indium tin oxide (ITO) and conductive fabric doped with conductive fibers. These materials are suitable for forming an electric field, supporting high current density charge transfer and withstanding electrostatic breakdown between electrodes.

[0021] The discharge-enhanced high-efficiency mechanical energy harvesting device as described above further includes an output management circuit, which is connected to both the first electrode and the second electrode.

[0022] In the above-described discharge-enhanced high-efficiency mechanical energy harvesting device, the output management circuit (for enhancing charge accumulation or regulating discharge characteristics to enhance energy output) includes a load resistor and an N-stage voltage multiplier circuit, where N = 1-5; each stage of the voltage multiplier circuit includes a first capacitor, a second capacitor, a first diode, a second diode, and a third diode;

[0023] The anode of the first diode and the cathode of the second diode are connected to the first end of the first capacitor at the same time, the anode of the third diode is connected to the second end of the first capacitor, the cathode of the first diode is connected to the first end of the second capacitor, and the anode of the second diode and the cathode of the third diode are connected to the second end of the second capacitor at the same time;

[0024] One end of the load resistor is connected to the first electrode, and the other end is connected to the second end of the first capacitor of the N-stage voltage multiplier circuit; the first end of the second capacitor of the N-stage voltage multiplier circuit is connected to the second electrode.

[0025] The core function of the aforementioned output management circuit is to implement a multiplier-type charge replenishment mechanism, dynamically compensating the stored charge through exponential (power-of-two) charge pumping technology. Without this output management circuit, the charge accumulation process exhibits a long-term characteristic, triggering a single high-current discharge only after the charge reaches a threshold. This discontinuous discharge pattern can easily lead to output fluctuations. However, with the introduction of the output management circuit, its exponential charge pumping characteristics significantly shorten the charge recovery period after a breakdown event, enabling the system to quickly complete charge replenishment after each breakdown, thereby achieving high-frequency, uniform pulsed discharge. This mechanism effectively improves the temporal stability and repeatability of the discharge behavior by optimizing the charge replenishment dynamics, providing the system with more reliable energy output.

[0026] In the above-described discharge-enhanced high-efficiency mechanical energy harvesting device, the resistance of the load resistor is 1Ω-100GΩ, and the capacitance of the first capacitor and the second capacitor is 1-100nF.

[0027] The discharge-enhanced high-efficiency mechanical energy harvesting device described above further includes an environmental control module, which is used to adjust the gas composition or pressure during electrostatic breakdown, such as nitrogen or helium within the range of 1Pa-2atm, to optimize discharge performance.

[0028] The present invention also provides a discharge-enhanced high-efficiency mechanical energy collection method, which applies a mechanical force to a discharge-enhanced high-efficiency mechanical energy collection device as described in any of the above items, triggering electrostatic breakdown to generate a discharge current, and then the discharge current is collected by the first electrode and the second electrode.

[0029] As the preferred technical solution:

[0030] In the discharge-enhanced high-efficiency mechanical energy harvesting method described above, the mechanical force is generated in the form of vibration, pressing, bending, stretching, friction, fluid drive or sound waves.

[0031] In the above-mentioned discharge-enhanced high-efficiency mechanical energy harvesting method, the current density of the discharge current collected by the first electrode and the second electrode is 0.1-2.5A / cm 2 ;The maximum average power density of mechanical energy converted into electrical energy is greater than or equal to 0.2Wm -2 Hz -1 , the maximum energy conversion efficiency is greater than or equal to 1.69%.

[0032] Beneficial effects:

[0033] This invention creates a low-resistance conductive path through a dielectric layer, allowing the discharge current generated by electrostatic breakdown to flow through it. This channel is then transported directly to the electrodes for collection, forming a conduction current. Compared to traditional displacement currents that rely on a slow electrostatic induction process, this effectively increases the current flow throughout the circuit and the current density of the mechanical energy harvesting device. The channel's low internal resistance of approximately 15Ω enables reversible impedance switching for electrode-to-electrode discharge, significantly reducing the device's internal resistance. During force-to-electricity conversion, the dielectric layer insulates and stores charge, and voltage accumulation triggers plasma discharge. The plasma's high conductivity allows for efficient energy release, improving energy conversion efficiency and increasing the energy share of electrical appliances. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the discharge-enhanced high-efficiency mechanical energy harvesting device of Example 2 after an output management circuit is added;

[0035] Figure 2 a and b are physical images of the composite structure A and composite structure B of Example 2, respectively;

[0036] Figure 3 Where a and b are the test results of the current density and maximum average power density of the discharge-enhanced high-efficiency mechanical energy harvesting device of Example 2, respectively;

[0037] Figure 4 Figure a is a graph showing the relationship between dielectric layer b of varying thicknesses and the maximum peak current (curves corresponding to right-facing arrows) and maximum peak voltage (curves corresponding to left-facing arrows) within a cycle after the discharge-enhanced, high-efficiency mechanical energy harvesting device of Example 2 is equipped with an output management circuit. Figures b and c are actual photographs of the discharge-enhanced, high-efficiency mechanical energy harvesting device of Example 2 driven by a fluorescent lamp and a light-emitting filament after the output management circuit is added.

[0038] Figure 5 a is the test result of the current density of the mechanical energy harvesting device of Comparative Example 1, b is the test result of the maximum average power density of the mechanical energy harvesting device of Comparative Example 1, and c is a comparison chart of the maximum energy conversion efficiency of Example 2 and Comparative Example 1;

[0039] Figure 6 A schematic diagram of the core working principle of the discharge-enhanced high-efficiency mechanical energy harvesting device of Example 2 after adding an output management circuit (taking an N-order voltage multiplier circuit as a 1st-order voltage multiplier circuit as an example);

[0040] Among them, 1 is the second electrode, 2 is the dielectric layer c, 3 is the dielectric layer b, and 4 is the first electrode. DETAILED DESCRIPTION

[0041] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0042] To ensure that the properties of the materials used in each embodiment and comparative example are fully disclosed, the present invention specifies the manufacturer information of the materials; in addition, products of other manufacturers that meet the requirements of the present invention are also applicable.

[0043] The following are the test methods for the relevant performance indicators in each embodiment and comparative example:

[0044] Porosity: A Micromeritics AutoPore V 9620 mercury intrusion porosimeter was used for testing according to GB / T 21650.1-2008, "Determination of Pore Size Distribution and Porosity of Solid Materials by Mercury Intrusion and Gas Adsorption Methods - Part 1: Mercury Intrusion Porosimetry." The porosity (%) was calculated using the following formula:

[0045] P ;

[0046] Where V p is the pore volume per unit mass of the sample (unit: cm 3 / g), obtained by integrating mercury intrusion data; V t is the total volume of the sample per unit mass (unit: cm 3 / g), obtained from the actual measurement of sample density and morphology size.

[0047] Relative dielectric constant: The test was conducted using a Turnkey broadband dielectric spectrometers Concept42 impedance analyzer in accordance with GB / T 5594.4-2015 "Test methods for properties of structural ceramic materials for electronic components - Part 4: Test method for dielectric constant and dielectric loss tangent", with a test frequency of 1Hz-1kHz and a test voltage of 1Vrms AC. r Calculated using the following formula:

[0048] ;

[0049] Where C is the measured capacitance (unit: F); d is the sample thickness (unit: m); S is the vertical projection area of ​​the electrode of the test instrument (unit: m²); 𝜀0 is the vacuum dielectric constant, 𝜀0=8.854×10 −12 F / m.

[0050] Current density, maximum average power density, maximum energy conversion efficiency: Use a wire to connect the first electrode, load resistor (resistance is 1-10 5 Ω), and the second electrode are connected in sequence. A Keysight N2893A current probe is clamped on the wire (connected in series in the loop). While applying mechanical force, a DSOX3012T oscilloscope is used to record the transient current waveform within 5 cycles and read the maximum peak current I (in A).

[0051] When testing the current density, the load resistor is set to 1Ω and the current density is calculated according to the following formula:

[0052] ;

[0053] Where J is the current density in A / cm²; I is the maximum peak current within 5 cycles in A; is the vertical projection area of ​​the first electrode (or second electrode), in cm²;

[0054] The average power density is calculated according to the following formula:

[0055] p ×10 -4 ;

[0056] ;

[0057] ;

[0058] Where p is the average power density, in Wm -2 Hz -1 ; is the average output power, in W; I(t) is the instantaneous current, in A; T is the duration of a single cycle, in s; R is the resistance of the load resistor, in Ω; f is the frequency, in Hz;

[0059] In 1-10 5 Within the range of Ω, adjust the resistance of the load resistor point by point, calculate the average power density corresponding to each resistor, and take the maximum value of all the results, that is, the maximum average power density;

[0060] Energy conversion efficiency refers to the ability of an energy harvester to convert mechanical input energy into electrical energy. It is defined as the ratio of output power to input power per unit time and is calculated as follows:

[0061]

[0062]

[0063] ;

[0064] Where, is the energy conversion efficiency, unit is %; P input is the input power, in W; is the magnitude of the applied mechanical force, in N; is the average speed of periodic reciprocating motion, in m / s; is the maximum relative displacement between the first electrode and the second electrode, in m;

[0065] In 1-10 5 Within the range of Ω, adjust the resistance of the load resistor point by point, calculate the energy conversion efficiency corresponding to each resistor, and take the maximum value of all results, that is, the maximum energy conversion efficiency.

[0066] Example 1

[0067] A discharge-enhanced high-efficiency mechanical energy harvesting device comprises a first electrode, a second electrode, a dielectric layer a, and an environmental control module;

[0068] The first electrode and the second electrode are both copper foils with a thickness of 10 μm. The dielectric layer a, the first electrode, and the second electrode have the same shape and are arranged horizontally, with a vertical projection area of ​​24 cm².

[0069] The dielectric layer a and the second electrode have the characteristic of causing electrostatic breakdown due to charge accumulation under mechanical force;

[0070] The dielectric layer a has a thickness of 50 μm and a relative dielectric constant of 3. The dielectric layer a has pores for the discharge current generated by electrostatic breakdown to pass through and be collected by the first electrode and the second electrode. The pores have a porosity of 80% and a pore diameter of 1-3 μm.

[0071] The environmental control module is used to adjust the gas composition or pressure during electrostatic breakdown;

[0072] The forming and compounding process of the dielectric layer a is as follows:

[0073] (1) Preparation of materials;

[0074] PVDF (polyvinylidene fluoride): manufacturer is Arkema GmbH, brand name is Kynar® HSV900;

[0075] DMF (N,N-dimethylformamide): CAS number 68-12-2, purity ≥99.8%;

[0076] Acetone: CAS number 67-64-1, purity ≥99.5%;

[0077] Teflon tape: manufacturer is 3M, brand is 3M™ 5480 PTFE Film Tape;

[0078] (2) Preparation of spinning solution;

[0079] The concentration of the spinning solution was 18 wt %, the solute was PVDF, and the solvent was a mixture of DMF and acetone in a mass ratio of 3:2;

[0080] (3) Electrospinning the spinning solution to form a dielectric layer a on the first electrode to obtain a composite structure, then hot pressing the edges of the composite structure at a pressure of 0.5 MPa and a temperature of 80°C to remove air, then sealing the edges of the composite structure with Teflon tape, then laying the composite structure horizontally on a workbench (with the dielectric layer a on top and the first electrode on the bottom), and then placing the second electrode on the composite structure, keeping the vertical projections of the first electrode, the second electrode and the dielectric layer a completely overlapped;

[0081] The electrospinning process parameters are as follows: spinning voltage 15 kV, spinning distance 25 cm, and propulsion speed 1 mL / h.

[0082] In an environment with a relative humidity of 20% (air atmosphere, pressure of 0.1 MPa), a mechanical force (1 N, frequency of 2 Hz, contact-separation form) was applied to the collection device of this embodiment. During this process, the dielectric layer a and the second electrode produced charge separation and voltage accumulation due to the mechanical force, and a conductive path was formed in the air through plasma discharge, converting mechanical energy into electrical energy. The current density of the discharge current collected by the first electrode and the second electrode was 0.5 A / cm 2 The maximum average power density of mechanical energy converted into electrical energy is 0.32Wm -2 Hz -1 , the maximum energy conversion efficiency is 2.78%.

[0083] Example 2

[0084] A discharge-enhanced high-efficiency mechanical energy harvesting device, such as Figure 1 As shown, it includes a first electrode 4, a second electrode 1, a dielectric layer b 3, a dielectric layer c 2, and an environmental control module;

[0085] The first electrode 4 and the second electrode 1 are both aluminum foils, each with a thickness of 0.1 mm. The dielectric layer b 3, the dielectric layer c 2, the first electrode 4, and the second electrode 1 have the same shape and are arranged horizontally, with a vertical projection area of ​​24 cm².

[0086] The dielectric layer b3 and the dielectric layer c2 have the characteristic of causing electrostatic breakdown due to charge accumulation under mechanical force;

[0087] The dielectric layer b3 has a thickness of 50 μm and a relative dielectric constant of 3; the dielectric layer c2 has a thickness of 30 μm and a relative dielectric constant of 2.5. Both dielectric layers b3 and c2 have channels through which discharge current generated by electrostatic breakdown passes and is subsequently collected by the first electrode 4 and the second electrode 1. The porosity of dielectric layer b3 is 80%, and the pore size is 2-4 μm; the porosity of dielectric layer c2 is 70%, and the pore size is 3-7 μm.

[0088] The environmental control module is used to adjust the gas composition or pressure during electrostatic breakdown;

[0089] The forming and compounding process of dielectric layer b and dielectric layer c is as follows:

[0090] (1) Preparation of materials;

[0091] PVDF: manufacturer is Arkema GmbH, brand name is Kynar® HSV900;

[0092] DMF: CAS number is 68-12-2, purity ≥99.8%;

[0093] Acetone: CAS number 67-64-1, purity ≥99.5%;

[0094] PA11 (polyamide 11): manufacturer is Arkema, brand is ArkemaRilsan®BESNOP40;

[0095] Formic acid: CAS number 64-18-6, purity ≥98%;

[0096] Dichloromethane: CAS number 75-09-2, purity ≥99.5%;

[0097] Teflon tape: manufacturer is 3M, brand is 3M™ 5480 PTFE Film Tape;

[0098] (2) Preparing spinning solution A and spinning solution B;

[0099] The concentration of spinning solution A was 18 wt %, the solute was PVDF, and the solvent was a mixture of DMF and acetone in a mass ratio of 3:2;

[0100] The concentration of spinning solution B is 7 wt %, the solute is PA11, and the solvent is a mixture of formic acid and dichloromethane with a mass ratio of 2:1;

[0101] (3) First, electrospin the spinning solution A once, deposit the dielectric layer b on the first electrode to obtain the composite structure A, and at the same time, electrospin the spinning solution B twice, deposit the dielectric layer c on the second electrode to obtain the composite structure B, and then heat press the edge of the composite structure A at a pressure of 0.5 MPa and a temperature of 80°C to exclude air, and at the same time, heat press the edge of the composite structure B at a pressure of 0.5 MPa and a temperature of 80°C to exclude air, and then seal the edge of the composite structure A with Teflon tape, and at the same time, seal the edge of the composite structure B with Teflon tape, and then lay the composite structure A horizontally on the workbench (dielectric layer b on top, first electrode on bottom), and then place the composite structure B on the composite structure A (dielectric layer c on bottom, second electrode on top), keeping the vertical projections of the composite structures A and B completely overlapping;

[0102] The process parameters of the primary electrospinning were: spinning voltage 15 kV, spinning distance 25 cm, and propulsion speed 1 mL / h; the process parameters of the secondary electrospinning were: spinning voltage 25 kV, spinning distance 20 cm, and propulsion speed 0.5 mL / h.

[0103] In an environment with a relative humidity of 20% (air atmosphere, pressure of 0.1 MPa), a mechanical force (0.4 N, frequency of 2 Hz, contact-separation form) was applied to the collection device of this embodiment. During this process, the dielectric layer b and the dielectric layer c produced charge separation and voltage accumulation due to the mechanical force. A conductive path was formed in the air through plasma discharge, converting mechanical energy into electrical energy. The current density of the discharge current collected by the first electrode and the second electrode was 2.5 A / cm 2 (like Figure 3 The maximum average power density of mechanical energy converted into electrical energy is 4.46Wm -2 Hz -1 (like Figure 3 As shown in b), the maximum energy conversion efficiency is 19.12% (as shown in Figure 5 (as shown in c).

[0104] Example 3

[0105] A discharge-enhanced high-efficiency mechanical energy harvesting device comprises a first electrode, a second electrode, a dielectric layer b, a dielectric layer c, and an environmental control module;

[0106] The first and second electrodes are both aluminum foils, each with a thickness of 20 μm. The dielectric layer b, dielectric layer c, first electrode, and second electrode have the same shape and are arranged horizontally, with a vertical projection area of ​​1 cm².

[0107] The dielectric layer b and the dielectric layer c have the characteristic of causing electrostatic breakdown due to charge accumulation under mechanical force;

[0108] The dielectric layer b has a thickness of 50 μm and a relative dielectric constant of 3; the dielectric layer c has a thickness of 10 μm and a relative dielectric constant of 10; both dielectric layers b and c are provided with channels for the discharge current generated by electrostatic breakdown to pass through and be collected by the first electrode and the second electrode; the dielectric layer b has a porosity of 80% and a pore size of 2-4 μm; the dielectric layer c has a porosity of 60% and a pore size of 0.2-1 μm;

[0109] The environmental control module is used to adjust the gas composition or pressure during electrostatic breakdown;

[0110] The forming and compounding process of dielectric layer b and dielectric layer c is as follows:

[0111] (1) Preparation of materials;

[0112] PVDF: manufacturer is Arkema GmbH, brand name is Kynar® HSV900;

[0113] DMF: CAS number is 68-12-2, purity ≥99.8%;

[0114] Acetone: CAS number 67-64-1, purity ≥99.5%;

[0115] MWCNT (multi-walled carbon nanotube): diameter 10-30 nm, length 5-15 μm, purchased from Carbon Yuan Technology Co., Ltd.

[0116] Dispersant: SDS (sodium dodecyl sulfate);

[0117] Deionized water;

[0118] Teflon tape: manufacturer is 3M, brand is 3M™ 5480 PTFE Film Tape;

[0119] (2) Preparation of spinning solution and spraying solution;

[0120] The concentration of the spinning solution was 18 wt %, the solute was PVDF, and the solvent was a mixture of DMF and acetone in a mass ratio of 3:2;

[0121] The spraying liquid was prepared by ultrasonic dispersion of MWCNT, SDS and deionized water. The concentration of MWCNT was 10 mg / mL and the concentration of SDS was 0.5 wt %.

[0122] (3) First, electrospin the spinning solution and deposit a dielectric layer b on the first electrode to obtain a composite structure A (the actual structure is shown in FIG. Figure 2 As shown in a), the spraying liquid is sprayed onto the second electrode to form a dielectric layer c to obtain a composite structure B (the actual structure is shown in Figure 2 (as shown in (b)), then hot pressing the edge of composite structure A at a pressure of 0.5 MPa and a temperature of 80°C to expel air, and simultaneously hot pressing the edge of composite structure B at a pressure of 0.5 MPa and a temperature of 80°C to expel air, then sealing the edge of composite structure A with Teflon tape, and simultaneously sealing the edge of composite structure B with Teflon tape, then laying composite structure A horizontally on a workbench (with dielectric layer b on top and the first electrode on the bottom), then horizontally placing composite structure B above composite structure A (with dielectric layer c on the bottom and the second electrode on top) and maintaining a certain distance (3 mm) from composite structure A, so that the vertical projections of composite structures A and B completely overlap;

[0123] The electrospinning process parameters were as follows: spinning voltage 15 kV, spinning distance 25 cm, and propulsion speed 1 mL / h; the spraying process parameters were as follows: spraying distance 20 cm, propulsion speed 1 mL / min, and hot plate temperature 60°C.

[0124] In an environment with a relative humidity of 20% (air atmosphere, pressure of 0.1 MPa), a mechanical force (50 mN, frequency of 20 kHz, in the form of ultrasound) was applied to the collection device of this embodiment. During this process, the dielectric layer b and the dielectric layer c produced charge separation and voltage accumulation due to the mechanical force. A conductive path was formed in the air through plasma discharge, converting mechanical energy into electrical energy. The current density of the discharge current collected by the first electrode and the second electrode was 0.1 A / cm 2 The maximum average power density of mechanical energy converted into electrical energy is 0.2Wm -2 Hz -1 , the maximum energy conversion efficiency is 1.69%.

[0125] Example 4

[0126] A discharge-enhanced high-efficiency mechanical energy harvesting device comprises a first electrode, a second electrode, a dielectric layer b, a dielectric layer c, and an environmental control module;

[0127] The first and second electrodes are both gold foils, each with a thickness of 10 μm. The dielectric layer b, dielectric layer c, first electrode, and second electrode have the same shape and are arranged horizontally, with a vertical projection area of ​​24 cm².

[0128] The dielectric layer b and the dielectric layer c have the characteristic of causing electrostatic breakdown due to charge accumulation under mechanical force;

[0129] The dielectric layer b has a thickness of 25 μm and a relative dielectric constant of 2; the dielectric layer c has a thickness of 30 μm and a relative dielectric constant of 3; both dielectric layers b and c are provided with channels for the discharge current generated by electrostatic breakdown to pass through and be collected by the first electrode and the second electrode; the porosity of dielectric layer b is 90% and the pore size is 1-3 μm; the porosity of dielectric layer c is 80% and the pore size is 3-6 μm;

[0130] The environmental control module is used to adjust the gas composition or pressure during electrostatic breakdown;

[0131] The forming and compounding process of dielectric layer b and dielectric layer c is as follows:

[0132] (1) Preparation of materials;

[0133] PVDF: manufacturer is Arkema GmbH, brand name is Kynar® HSV900;

[0134] DMF: CAS number is 68-12-2, purity ≥99.8%;

[0135] Acetone: CAS number 67-64-1, purity ≥99.5%;

[0136] GO (graphene oxide) dispersion: manufacturer: Aladdin, product number: G466617;

[0137] PVA (polyvinyl alcohol): manufacturer: Sigma-Aldrich, product number: 341584;

[0138] Deionized water;

[0139] Teflon tape: manufacturer is 3M, brand is 3M™ 5480 PTFE Film Tape;

[0140] (2) Preparing spinning solution A and spinning solution B;

[0141] The concentration of spinning solution A was 18 wt %, the solute was PVDF, and the solvent was a mixture of DMF and acetone in a mass ratio of 3:2;

[0142] Spinning solution B consists of GO dispersion, PVA, and deionized water. The concentration of GO dispersion is 1 wt%, and the concentration of PVA is 8 wt%.

[0143] (3) First, electrospin the spinning solution A once, deposit the dielectric layer b on the first electrode to obtain the composite structure A, and at the same time, electrospin the spinning solution B twice, deposit the dielectric layer c on the second electrode to obtain the composite structure B, and then heat press the edge of the composite structure A at a pressure of 0.5 MPa and a temperature of 80°C to exclude air, and at the same time, heat press the edge of the composite structure B at a pressure of 0.5 MPa and a temperature of 80°C to exclude air, and then seal the edge of the composite structure A with Teflon tape, and at the same time, seal the edge of the composite structure B with Teflon tape, and then lay the composite structure A horizontally on the workbench (dielectric layer b on top, first electrode on bottom), and then place the composite structure B on the composite structure A (dielectric layer c on bottom, second electrode on top), keeping the vertical projections of the composite structures A and B completely overlapping;

[0144] The process parameters of the primary electrospinning were: spinning voltage 15 kV, spinning distance 25 cm, and propulsion speed 1 mL / h; the process parameters of the secondary electrospinning were: spinning voltage 20 kV, spinning distance 20 cm, and propulsion speed 0.5 mL / h.

[0145] In an environment with a relative humidity of 20% (air atmosphere, pressure of 0.1 MPa), a mechanical force (1 N, frequency of 3 Hz, in the form of horizontal friction) was applied to the collection device of this embodiment. During this process, the dielectric layer b and the dielectric layer c produced charge separation and voltage accumulation due to the mechanical force. A conductive path was formed in the air through plasma discharge, converting mechanical energy into electrical energy. The current density of the discharge current collected by the first electrode and the second electrode was 0.7 A / cm 2 The maximum average power density of mechanical energy converted into electrical energy is 2.5Wm -2 Hz -1 , the maximum energy conversion efficiency is 14.29%.

[0146] Comparative Example 1

[0147] A mechanical energy harvesting device, which differs from Example 2 only in that: dielectric layer b and dielectric layer c are not provided with channels, and the forming and composite process of dielectric layer b and dielectric layer c is as follows: first, spinning solution A is spin-coated (speed 3000 rpm, time 30s) on the first electrode and then dried (100°C, 1h) to form dielectric layer b (thickness is the same as Example 2) to obtain composite structure A, and at the same time, spinning solution B is spin-coated (speed 3000 rpm, time 30s) on the second electrode and then dried (100°C, 1h) to form dielectric layer c (thickness is the same as Example 2) to obtain composite structure B, and then under pressure The edges of composite structure A were hot pressed at a pressure of 0.5 MPa and a temperature of 80°C to exclude air, and the edges of composite structure B were hot pressed at a pressure of 0.5 MPa and a temperature of 80°C to exclude air. The edges of composite structure A were then sealed with Teflon tape, and the edges of composite structure B were then sealed with Teflon tape. Composite structure A was then laid horizontally on a workbench (with dielectric layer b on top and the first electrode on the bottom), and composite structure B was then placed on composite structure A (with dielectric layer c on the bottom and the second electrode on top), keeping the vertical projections of composite structures A and B completely overlapping.

[0148] In an environment with a relative humidity of 20% (air atmosphere, pressure of 0.1 MPa), a mechanical force (0.4 N, frequency of 2 Hz, contact-separation form) was applied to the collection device of this comparative example. During this process, the dielectric layer b and the dielectric layer c produced charge separation and voltage accumulation due to the mechanical force, and a conductive path was formed in the air through plasma discharge, converting mechanical energy into electrical energy. The current density of the discharge current collected by the first electrode and the second electrode was 50 μA / cm 2 (like Figure 5 The maximum average power density of mechanical energy converted into electrical energy is 40.89mWm -2 Hz -1 (like Figure 5 As shown in b), the maximum energy conversion efficiency is 0.19% (as shown in Figure 5 (as shown in c).

[0149] Compared with Example 2, Comparative Example 1 shows significantly lower current density and maximum energy conversion efficiency. This is because the dielectric layers b and c in Comparative Example 1 lack pores, preventing them from forming a low-resistance conductive path for efficient discharge current flow. While the dielectric layer can produce charge separation and voltage accumulation under mechanical action, the plasma discharge path formed by electrostatic breakdown is difficult to maintain within the dense dielectric layer. The discharge current relies primarily on traditional electrostatic induction (primarily displacement current), which has low conduction efficiency and slow response. Furthermore, the non-porous structure significantly increases the internal resistance between the electrodes, hindering the charge accumulation and release process. Consequently, a significant amount of energy is lost due to impedance mismatch, preventing efficient conversion into usable electrical energy.

[0150] The discharge-enhanced high-efficiency mechanical energy harvesting device of the present invention can also be equipped with an output management circuit, such as Figure 1 As shown, the output management circuit includes a load resistor and an N-order voltage multiplier circuit, N=1-5; each order voltage multiplier circuit includes a first capacitor, a second capacitor, a first diode, a second diode and a third diode; the positive electrode of the first diode and the negative electrode of the second diode are simultaneously connected to the first end of the first capacitor, the positive electrode of the third diode is connected to the second end of the first capacitor, the negative electrode of the first diode is connected to the first end of the second capacitor, and the positive electrode of the second diode and the negative electrode of the third diode are simultaneously connected to the second end of the second capacitor; one end of the load resistor is connected to the first electrode, and the other end is simultaneously connected to the second end of the first capacitor of the N-order voltage multiplier circuit; the first end of the second capacitor of the N-order voltage multiplier circuit is simultaneously connected to the second electrode; the resistance value of the load resistor is 1Ω-100GΩ, and the capacitance value of the first capacitor and the second capacitor is 1-100nF.

[0151] like Figure 6 As shown, the discharge-enhanced, high-efficiency mechanical energy harvesting device of the present invention fully implements an "energy accumulation-release" closed loop: the device comprises a first electrode, a second electrode, and dielectric layers b and c therebetween. Pores are provided on the surfaces of dielectric layers b and c as low-resistance conductive pathways. Taking the collection device of Example 2 with the addition of an output management circuit as an example, during the energy accumulation phase, the output management circuit works synergistically with the first and second electrodes and dielectric layers b and c. Mechanical force induces charge separation between dielectric layers b and c, gradually accumulating a potential difference. The capacitor and diode in the voltage multiplier circuit form a charge pumping structure that, through synergistic series and parallel connections, continuously guides charge flow during the separation process, exponentially increasing the charge accumulation rate, causing the electric field strength between the dielectric layers b and c to more rapidly approach the air breakdown threshold and significantly shortening the breakdown response time. When the electric field between dielectric layers b and c reaches a critical value, the system triggers electrostatic breakdown, forming a plasma discharge pathway and releasing a high-intensity pulse current. This discharge current is rapidly conducted along the pre-set pores and efficiently collected by the first and second electrodes, respectively. At the same time, the charge stored in the voltage-doubling circuit is also released through the same pathway, enhancing the discharge current output and realizing a synergistic discharge mechanism. During the dynamic process of contact-separation, the charge difference between the electrodes drives the voltage-doubling circuit to continuously charge and discharge. The contact phase completes charge redistribution, and the separation phase drives further accumulation. The overall process achieves high-efficiency conversion from mechanical energy to electrical energy through the synergistic mechanism of "voltage-doubling circuit regulation + electrostatic breakdown triggering + efficient channel diversion," breaking through the traditional displacement current mechanism and constructing a charge collection mode with impedance adaptive capabilities.

[0152] The present invention also explores the effect of the thickness of the dielectric layer on the discharge-enhanced high-efficiency mechanical energy harvesting device. The harvesting device differs from Example 2 in that: an output management circuit is added, wherein the voltage multiplier circuit is of first order, the load resistor has a resistance of 1Ω, the capacitance of the first and second capacitors is 100nF, and the diode uses a 1N4007. In addition, the process parameters (spinning time) of the primary electrospinning are changed to change the thickness of the dielectric layer b.

[0153] The specific research process is as follows: a Keysight N2893A current probe is clamped on the conductor. While applying a mechanical force (1N, frequency of 2Hz, in the form of contact-separation), a DSOX3012T oscilloscope is used to record the transient current and transient voltage waveforms within 5 cycles, reading the maximum peak current I (unit: A) and maximum peak voltage U (unit: kV). Subsequently, the relationship between the dielectric layer b of different thicknesses and the maximum peak current and maximum peak voltage within the cycle is recorded and plotted. The results are shown in Figure 2. Figure 4 As shown in Figure a, it can be seen from the figure that as the thickness of the dielectric layer b increases, the maximum peak voltage and the maximum peak current both show a trend of first rising rapidly and then tending to be flat;

[0154] When the thickness of the dielectric layer b is 50 μm, the corresponding discharge-enhanced high-efficiency mechanical energy harvesting device converts mechanical energy into electrical energy through the output management circuit during the application of mechanical force, such as Figure 4 As shown in Figures b and c, the device easily drives 4×55W series fluorescent lamps and a 20W luminous filament, demonstrating that the device has a high voltage output capability, can effectively store and release energy, and can adapt to different power loads, verifying the feasibility of the device in driving loads in actual application scenarios.

Claims

1. A discharge-enhanced high-efficiency mechanical energy harvesting device comprising a first electrode, a second electrode, and a dielectric layer located therebetween; The number of the dielectric layer is one, denoted as dielectric layer a, the dielectric layer a is connected to the first electrode, and the dielectric layer a and the second electrode have the characteristic of inducing electrostatic breakdown due to charge accumulation under mechanical force; Alternatively, the number of dielectric layers is two, denoted as dielectric layer b and dielectric layer c, dielectric layer b is connected to the first electrode, dielectric layer c is connected to the second electrode, and dielectric layer b and dielectric layer c have the characteristic of inducing electrostatic breakdown due to charge accumulation under mechanical force; It is characterized by: Each dielectric layer is provided with a channel for the discharge current generated by electrostatic breakdown to pass through and then be collected by the first electrode and the second electrode; When the number of dielectric layers is one, the thickness of dielectric layer a is not less than 50 μm; When the number of dielectric layers is two, the sum of the thicknesses of dielectric layer b and dielectric layer c is not less than 50 μm; The thickness of the first electrode or the second electrode is 1 μm-10 cm; The first electrode, the second electrode and each dielectric layer are arranged horizontally, and the vertical projection area is greater than or equal to 1 cm 2 .

2. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 1, characterized in that: The porosity of each dielectric layer is 60-90%, and the pore size is 0.2-7 μm.

3. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 2, characterized in that: The material of each dielectric layer is polymer, metal oxide, carbon-based material or composite material, and the relative dielectric constant of each dielectric layer is greater than 2.

4. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 1, characterized in that: The materials of the first electrode and the second electrode are independently selected from one of copper, aluminum, gold, silver, graphene, carbon nanotubes, poly (3,4-ethylenedioxythiophene), polypyrrole, indium tin oxide, and conductive fabric doped with conductive fibers.

5. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 1, characterized in that: The device also includes an output management circuit, which is connected to the first electrode and the second electrode at the same time.

6. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 5, characterized in that: The output management circuit includes a load resistor and an N-stage voltage multiplication circuit, where N=1-5; each stage voltage multiplication circuit includes a first capacitor, a second capacitor, a first diode, a second diode, and a third diode; The anode of the first diode and the cathode of the second diode are connected to the first end of the first capacitor at the same time, the anode of the third diode is connected to the second end of the first capacitor, the cathode of the first diode is connected to the first end of the second capacitor, and the anode of the second diode and the cathode of the third diode are connected to the second end of the second capacitor at the same time; One end of the load resistor is connected to the first electrode, and the other end is connected to the second end of the first capacitor of the N-stage voltage multiplier circuit; the first end of the second capacitor of the N-stage voltage multiplier circuit is connected to the second electrode.

7. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 6, characterized in that: The resistance of the load resistor is 1Ω-100GΩ, and the capacitance of the first capacitor and the second capacitor is 1-100nF.

8. The discharge-enhanced high-efficiency mechanical energy harvesting device according to claim 1, characterized in that: It also includes an environmental control module, which is used to adjust the gas composition or pressure during electrostatic breakdown.

9. A discharge-enhanced high-efficiency mechanical energy harvesting method, characterized in that: A mechanical force is applied to the discharge-enhanced high-efficiency mechanical energy harvesting device according to any one of claims 1 to 8 to induce electrostatic breakdown to generate a discharge current, which is then collected by the first electrode and the second electrode.

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