阅读说明：本技术 一种静态静电电压源装置及其制备方法 (Static voltage source device and preparation method thereof ) 是由 徐子盛 鄂世举 包昆伟 邸奎 陈浩杰 于 2021-07-08 设计创作，主要内容包括：本发明公开了一种静态静电电压源装置及其制备方法,属于能量收集和自驱动传感器领域。包括静电电压源、外接电容器和整流桥。静电电压源由驻极体与其两侧的电极组成,利用驻极体和静电感应原理,将两个电极分别放置于距离带电驻极体层上下的不同距离处,两个电极感应出不同量的电荷从而具有不同的电势,两电极之间具有一定的电势差。将驻极体两侧的电极接入整流桥的输入端,将外接电容器接入整流桥的输出端,即可通过静电电压源为外接电容器充电,无需额外做功。本发明具有结构简单和方便智能的特点,可用于自驱动传感领域和能量转换领域。(The invention discloses a static voltage source device and a preparation method thereof, and belongs to the field of energy collection and self-driven sensors. Comprises an electrostatic voltage source, an external capacitor and a rectifier bridge. The static voltage source is composed of an electret and electrodes on two sides of the electret, the two electrodes are respectively placed at different distances from the upper part and the lower part of a charged electret layer by utilizing the principles of the electret and static induction, the two electrodes induce different amounts of charges so as to have different electric potentials, and a certain electric potential difference is formed between the two electrodes. The electrodes on two sides of the electret are connected into the input end of the rectifier bridge, the external capacitor is connected into the output end of the rectifier bridge, the external capacitor can be charged through the electrostatic voltage source, and extra work is not needed. The invention has the characteristics of simple structure, convenience and intelligence, and can be used in the fields of self-driven sensing and energy conversion.)

1. A static electrostatic voltage source device is characterized by comprising an electrostatic voltage source (1), an external capacitor (3) and a rectifier bridge (2); the electrostatic voltage source (1) consists of an electret film (4) and an upper electrode (6) and a lower electrode (5) which are arranged on two sides of the electret film, the upper electrode (6) and the lower electrode (5) have charges with different charge amounts and the same type, a charged layer of the electret film (4) has charges opposite to those of the upper electrode (6) and the lower electrode (5), the upper electrode (6) and the lower electrode (5) are metal electrodes, and the distances between the upper electrode and the electret film charged layer are different from those between the lower electrode and the electret film charged layer;

the upper electrode (6) and the lower electrode (5) are respectively connected to the input side of the rectifier bridge (2), and the two sides of the external capacitor (3) are respectively connected to the output side of the rectifier bridge (2).

2. The static electrostatic voltage source device according to claim 1, wherein the material of said upper electrode and said lower electrode is copper, gold, aluminum, silver or their nanowires.

3. The static electrostatic voltage source device according to claim 1, wherein said electret film material is selected from any one of polyvinylidene fluoride, perfluoroethylene propylene copolymer, polyimide, polychlorotrifluoroethylene, polypropylene, polyethylene, cycloolefin copolymer, soluble polytetrafluoroethylene, polyvinyl fluoride, parylene.

4. The static electrostatic voltage source according to claim 1, wherein a support structure is provided between the electret film and the upper electrode and/or between the electret film and the lower electrode.

5. A static electrostatic voltage source device according to claim 1, wherein a dielectric material (7) is provided between the electret film and the lower electrode.

6. The static electrostatic voltage source device according to claim 1, wherein said external capacitor (3) is an elastically stretchable capacitor, and is formed by a dielectric elastomer and electrodes on both sides thereof, and said dielectric elastomer is an elastically stretchable material.

7. The static electrostatic voltage source device according to claim 6, wherein said dielectric elastomer material is selected from any one of silicone rubber, block copolymer, thermoplastic bio-plastic, and said electrodes on both sides thereof are selected from any one of conductive silicone grease, silver nanowire, hydrogel, and ion conductor.

8. The static electrostatic voltage source device according to claim 1, wherein said rectifier bridge is built up of four low on-voltage diodes.

9. A method of manufacturing a static electrostatic voltage source device according to claim 1, comprising the steps of:

1) preparing an electrostatic voltage source: plating a gold electrode on one surface of the electret film by using a magnetron sputtering instrument to be used as an upper electrode; charging the electrode-free surface of the electret film by negative corona polarization of 10kV for 1-10 min to make the surface potential higher than 50V; attaching one surface of the electret film with negative charges to a lower electrode; the electret films with negative charges respectively induce different amounts of positive charges on the upper electrode and the lower electrode, and a potential difference is formed between the upper electrode and the lower electrode;

2) connecting an electrostatic voltage source with a rectifier bridge, enabling an upper electrode and a lower electrode to be respectively connected with an input side of the rectifier bridge, respectively connecting two sides of an external capacitor with an output side of the rectifier bridge, converting potential difference between the same-sign charges of the upper electrode and the lower electrode into positive and negative charge potential difference through the rectifier bridge, and charging the external capacitor (3) under the action of electrostatic voltage, wherein voltages at two ends of the external capacitor (3) meet the following formula:

wherein V represents the voltage across the external capacitor, d₁Denotes the thickness of the electret film, d₂The distances between the lower electrode and the electret film, C and C are shown_ERespectively representing the capacitance of the electrostatic voltage source and the capacitance of the external capacitor,. epsilon₀The dielectric constant in vacuum, S represents the area of the electret film, and σ represents the surface charge density.

10. A method of manufacturing a static electrostatic voltage source device according to claim 9, wherein the electret film is charged by corona charging, tribocharging, contact polarization, liquid polarization or high temperature polarization.

Technical Field

The invention belongs to the field of energy sources, and particularly relates to a static voltage source device and a preparation method thereof.

Background

With the application of massive distributed sensors, especially the increasing demand on energy supply of the sensors, a stable energy supply application technology has become one of the important research contents in the field of energy storage. Among them, the development of high energy density batteries and capacitors to improve the operation time thereof is a current research focus. However, batteries and capacitors cannot stably store electric charges for a long period of time due to limitations of a storage mechanism. Meanwhile, in a humid and humid environment, the electrochemical cell needs to be packaged to protect the cell so as to ensure stable working operation of the cell. Therefore, it is crucial to find a stable energy supply device.

Disclosure of Invention

In view of the above-mentioned drawbacks and needs in the prior art, the present invention provides a static electrostatic voltage source device and a method for manufacturing the same, which aims to implement a low-cost semi-permanent voltage source suitable for complex environments.

In order to achieve the purpose, the invention adopts the technical scheme that:

one of the objectives of the present invention is to provide a static voltage source device, which includes a static voltage source, an external capacitor and a rectifier bridge; the electrostatic voltage source consists of an electret film, an upper electrode and a lower electrode which are arranged on two sides of the electret film, the upper electrode and the lower electrode have the same type of charges with different charge quantities, a charged layer of the electret film has charges opposite to those of the upper electrode and the lower electrode, the upper electrode and the lower electrode are metal electrodes, and the distances between the upper electrode and the charged layer of the electret film and the distances between the lower electrode and the charged layer of the electret film are different;

the upper electrode and the lower electrode are respectively connected to the input side of the rectifier bridge, and the two sides of the external capacitor are respectively connected to the output side of the rectifier bridge.

Preferably, the materials of the upper electrode and the lower electrode are copper, gold, aluminum, silver and nanowires thereof.

Preferably, the upper electrode is prepared by plating a metal layer on the upper surface of the electret film.

Preferably, a support structure is arranged between the electret film and the upper electrode and/or between the electret film and the lower electrode.

Preferably, a dielectric material is disposed between the electret film and the lower electrode.

Preferably, the external capacitor is an elastic stretchable capacitor and is formed by coating conductive grease on two sides of a dielectric elastomer material.

Preferably, the rectifier bridge is built by four low-conducting-voltage diodes.

Another objective of the present invention is to provide a method for manufacturing the static electrostatic voltage source device, including the following steps:

1) preparing an electrostatic voltage source: plating a gold electrode on one surface of the electret film by using a magnetron sputtering instrument to be used as an upper electrode; charging the electrode-free surface of the electret film by negative corona polarization of 10kV for 1-10 minutes to ensure that the surface of the electret film is negatively charged and the surface potential is higher than 50V; attaching one surface of the electret film with negative charges to a lower electrode; the electret films with negative charges respectively induce different amounts of positive charges on the upper electrode and the lower electrode, and a potential difference is formed between the upper electrode and the lower electrode;

2) connecting an electrostatic voltage source with a rectifier bridge, enabling an upper electrode and a lower electrode to be respectively connected with an input side of the rectifier bridge, respectively connecting two sides of an external capacitor with an output side of the rectifier bridge, converting potential difference between the same-sign charges of the upper electrode and the lower electrode into positive and negative charge potential difference through the rectifier bridge, and charging the external capacitor (3) under the action of electrostatic voltage, wherein voltages at two ends of the external capacitor (3) meet the following formula:

wherein V represents the voltage across the external capacitor, d₁Denotes the thickness of the electret film, d₂The distances between the lower electrode and the electret film, C and C are shown_ERespectively representing the capacitance of the electrostatic voltage source and the capacitance of the external capacitor,. epsilon₀The dielectric constant in vacuum, S represents the area of the electret film, and σ represents the surface charge density.

Compared with the prior art, the invention has the advantages that:

(1) compared with a chemical voltage source, the static electrostatic voltage source adopts an electret material which can be semi-permanently charged, so that the stability is higher;

(2) compared with electrostatic generators such as electret generators, friction nano-discharge machines and piezoelectric generators, the static electrostatic voltage source charges an external capacitance device through the rectifier bridge until the voltage is balanced, and external force does not need to be additionally applied to press the external capacitance device in the process. Furthermore, the static electrostatic voltage source can be more diversified in structure and wider in application range.

Drawings

FIG. 1 is a schematic diagram of a static electrostatic voltage source device according to the present invention;

FIG. 2 is a voltage-time diagram of the 100nF capacitor charging of the present embodiment;

FIG. 3 is a graph showing the change in capacitance voltage with time after the 100nF capacitor of the present embodiment is charged;

fig. 4 is a schematic diagram of a static electrostatic voltage source device structure a in this embodiment, in which an upper electrode is tightly attached to an electret film, and a certain distance is left between a lower electrode and the electret film;

FIG. 5 is a schematic diagram of a static electrostatic voltage source device structure b in the present embodiment, in which other dielectric materials are filled between the electret film and the lower electrode;

fig. 6 is a schematic diagram of a static electrostatic voltage source device structure c in the present embodiment, in which a support structure is added between the electret film and the upper electrode, and between the electret film and the lower electrode, respectively;

fig. 7 is a schematic diagram of a static electrostatic voltage source device structure d in the present embodiment, in which only a support structure is added between the electret film and the upper electrode.

FIG. 8 is a schematic diagram of an apparatus in which the external capacitor of the static voltage source is an elastic capacitor according to the present embodiment;

fig. 9 is a schematic diagram of the voltage variation of the stretching process of the elastomer capacitor in this embodiment.

In the figure: 1-electrostatic voltage source, 2-rectifier bridge, 3-external capacitor, 4-electret film, 5-lower electrode, 6-upper electrode, 7-dielectric material, 8-dielectric elastomer and 9-conductive grease.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

The static electrostatic voltage source device provided by the embodiment comprises: an electrostatic voltage source 1 composed of a charged electret and upper and lower electrodes, a rectifier bridge 2 and an external capacitor 3, as shown in fig. 1. Firstly, plating a gold electrode on one surface of Polytetrafluoroethylene (PTFE) of an electret film 4 by a magnetron sputtering instrument to serve as an upper electrode 6, and then polarizing by negative corona of 10kV to give an area of 9cm²The electret film Polytetrafluoroethylene (PTFE) having a thickness of 50 μm is charged without electrode, and the surface thereof is negatively charged. Then, the surface having negative charges and the surface of the substrate having the copper electrode as the lower electrode 5 were bonded to each other, thereby forming the electrostatic voltage source 1 of the present invention. In this embodiment, the distances between the upper electrode 6 and the lower electrode 5 and the electret film charged layer are different.

According to the electrostatic induction principle, the electret film material is negatively charged, and the electrodes on the two sides are respectively placed at different distances from the upper part and the lower part of the charged electret layer, so that positive charges with different quantities are induced by the upper electrode and the lower electrode, so that different electric potentials are obtained, and a potential difference is formed between the two electrodes. The electrodes on the two sides of the electret are connected with the input end of the rectifier bridge 2, so that the potential difference between the same number of charges can be converted into the potential difference of positive and negative charges, and the output end of the rectifier bridge 2 is connected with the external capacitor 3 with the capacitance of 100 nF. Under the action of the electrostatic voltage, the external capacitor 3 can be charged by the electrostatic voltage source 1, and the charging process is shown as a 100nF capacitance charging voltage-time diagram in FIG. 2. This embodiment also provides a schematic diagram of the capacitance voltage over time as shown in fig. 3, which can maintain a stable charge for a long period of time after charging the 100nF capacitor. The static voltage source does not need to be additionally processed, and the switched capacitor is static.

The voltage at the two ends of the external capacitor 3 meets the following formula:

wherein V represents the voltage across the external capacitor 3, d₁Denotes the thickness of the electret film, d₂Distances of the lower electrode from the electret film (see FIG. 4), C and C are shown_ECapacitance representing electrostatic voltage source and capacitance, epsilon, of external capacitor₀The dielectric constant in vacuum, S represents the area of the electret film, and σ represents the surface charge density.

In this example, d₁、d₂As shown in fig. 4, is not limited in scope.

The electret materials include but are not limited to polyvinylidene fluoride (PVDF), perfluoroethylene propylene copolymer (FEP), Polyimide (PI), Polychlorotrifluoroethylene (PCTFE), polypropylene (PP), Polyethylene (PE), cycloolefin copolymer (COC), soluble Polytetrafluoroethylene (PFA), polyvinyl fluoride (E-TFE), Parylene (Parylene) and other electret materials.

The electrode material includes, but is not limited to, copper, gold, aluminum, silver, nanowires thereof, and other electrode materials.

In one embodiment of the present invention, the electret film 4 and the lower electrode 5 may be filled with another dielectric material 7, as shown in fig. 5. The dielectric material comprises acrylic acid VHB4905 or polydimethylsiloxane.

The distance between the upper and lower electrodes of the static voltage source 1 and the electret is not limited to this embodiment, and the static voltage source may be constructed by using a supporting structure, as shown in fig. 6-7, wherein fig. 6 is that a supporting structure is added between the electret film and the upper electrode, and between the electret film and the lower electrode, respectively; fig. 7 is a schematic diagram of the addition of support structures only between the electret film and the upper electrode. The support structure comprises an insulating inorganic substance and an insulating polymer.

In one embodiment of the invention, the charging may be by means of different polarization means, such as positive and negative high voltage corona polarization. Taking a corona polarization process as an example, an electret film is placed at a position 3-10cm below a corona needle, high voltage of 10-20kV is applied to the corona needle, the corona needle generates point discharge, charges are driven to the surface of an electret material by an electric field and are finally captured by an electret, and the surface potential range of the electret film is as follows: 0- + -3 kV. The charging method of the electret material is not limited to corona charging, tribocharging, contact polarization, liquid polarization, high-temperature polarization, and the like.

Example 2

The static electrostatic voltage source device provided by the embodiment comprises: an electrostatic voltage source 1 composed of a charged electret, upper and lower electrodes, a rectifier bridge 2, and an external capacitor 3, as shown in fig. 8. Firstly, a magnetron sputtering instrument is used for plating a gold electrode on one surface of an electret film 4 of Polytetrafluoroethylene (PTFE) as an upper electrode 6, and then negative corona polarization of 10kV is carried out to give an area of 9cm²The electret film Polytetrafluoroethylene (PTFE) having a thickness of 50 μm is charged without electrode, and the surface thereof is negatively charged. Then, the surface having negative charges and the surface of the substrate having the copper electrode as a lower electrode are bonded to each other, thereby forming the electrostatic voltage source 1 of the present invention. In this embodiment, the distances between the upper electrode 6 and the lower electrode 5 and the electret film charged layer are different.

In this embodiment, the external capacitor 3 is composed of a dielectric elastomer 8 and electrodes on both sides thereof, the dielectric elastomer material may be silicone rubber such as polyacrylate PDMS, block copolymer such as SEBS, thermoplastic bioplastic such as Ecoflex, etc., the electrode material on both sides thereof may be conductive silicone grease, silver nanowire, hydrogel, ion conductor, etc., preferably, a combination of polyacrylate (VHB4905) and conductive grease 9 (japan shines), and is prepared by coating the flexible electrode material conductive grease on both upper and lower sides of the dielectric elastomer polyacrylate, and the external capacitor composed of the two is elastically stretchableCapacitance, which can be changed by stretching or the like. In this embodiment, the area of the elastically stretchable capacitor is 50cm²50 microns thick and 430pF capacitance. After a static electrostatic voltage source is connected, the voltage at two ends of the elastic stretchable capacitor can reach 14V. By means of stretching, the voltage is reduced to 7V, stretching is repeated, and the voltage changes along with the stretching, so that the static electrostatic voltage source system of the embodiment can be used in the field of self-driven sensing.

The principle is as follows: reference formulaWherein C, e, S and d are the capacitance, dielectric constant, area and dielectric elastomer thickness of the elastically stretchable capacitor, respectively, it can be seen that the elastically stretchable capacitance changes during the deformation process. Further, according to the formula Q ═ CU, where Q and U are the charge amount and the voltage of the elastically stretchable capacitor, respectively, it can be seen that, in the case of a certain charge amount, the voltage of the elastically stretchable capacitor changes due to the capacitance change of the elastically stretchable capacitor. In summary, during the stretching process along the electrode direction of the elastic stretchable capacitor, the capacitance value of the elastic stretchable capacitor becomes larger and the voltage thereof becomes smaller, whereas during the releasing process, the capacitance value becomes smaller and the voltage becomes larger.

The change of the voltage across the external capacitor 3 as shown in the figure satisfies the following formula

Wherein, V represents the voltage at two ends of the external capacitor, C and Q represent the capacitance value of the elastic capacitor and the charge quantity at two ends of the capacitor.

In this embodiment, the form of the external capacitor is not limited to the form of a commercial capacitor, and may be replaced by a variable capacitor such as an elastic capacitor, a voltage-variable capacitor, and the like, so as to be used in the field of self-driven sensing.

In this example, as shown in fig. 9, the feasibility of such an electrostatic voltage source for a self-driven sensor was verified. The high-flexibility dielectric elastomer capacitor is used as an external capacitor of the static voltage source, and the external elastic capacitor is periodically stretched to change the capacitance and further change the voltage. The voltage change reflects that a system formed by a static electrostatic voltage source and an external elastic capacitor can respond to the change, and further the system can be used as a self-driven sensor in the field of wearable flexible sensing.

The foregoing lists merely illustrate specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.