KR102507606B1 - Non-polar Liquid Lubricant Submerged Triboelectric Nanogenerator for Current Amplification via Direct Electron Flow - Google Patents

Abstract

The present invention relates to a triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow and an operating method thereof, and more particularly, to an internal cylinder having a dielectric; at least one plate electrode surrounding the outer surface of the inner cylinder to be spaced apart by a specific distance; a plurality of rolling electrodes positioned between the plate electrode and the inner cylinder; and a liquid lubricant filled in the space between the plate electrode and the inner cylinder.

Description

Non-polar Liquid Lubricant Submerged Triboelectric Nanogenerator for Current Amplification via Direct Electron Flow

The present invention relates to a triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow and an operating method thereof.

Triboelectric nanogenerators (TENG) can convert input mechanical energy into electrical energy output through Maxwell's displacement current representing current.

This potential of TENGs was demonstrated by analyzing the generation mechanism, fabricating materials with higher surface charge, and realizing micro/nanostructured surfaces to increase the surface area.

TENGs with increased output are used as auxiliary power sources for a variety of self-powered sensors for portable electronic devices, chemical and motion sensing. Despite these advantages, recent work can lead to air breakdown and low current output generation by certain limitations of high surface potential.

In particular, typical TENG structures are composed of electrodes and dielectric layers that exhibit relative motion, which can cause air breakdown and low current output. To alleviate electrical problems, some researchers have tried strategies such as changing the surrounding environment, using liquid to suppress air breakdown and inducing microplasma to ensure high current.

In addition, some known mechanical limitations of TENGs prevent exposure of the polymer dielectric to excessive input forces, either through mechanical design or the use of lubricants, which can significantly shorten TENG lifetime. Despite these efforts to address mechanical or electrical issues, the generation mechanism and structure must be further optimized to simultaneously address electrical and mechanical limitations.

Korean Registered Patent No. 10-1728472 Korean registered patent 10-1800091 Korean Registered Patent No. 10-1685184 Korean Registered Patent No. 10-2101085

Therefore, the present invention has been made to solve the above conventional problems, and according to an embodiment of the present invention, when non-polar liquid lubricating oil is filled in a triboelectric nanogenerator, air is destroyed due to the long Debye length of the lubricating oil. current through direct electron flow, and rolling friction and lubrication can greatly reduce the friction wear of the device, generating high voltage and current outputs of up to 200V and 170mA respectively, which can charge commercial capacitors and batteries. Its purpose is to provide a triboelectric nanogenerator with a liquid lubricant for amplification and its operating method.

And according to the embodiment of the present invention, the frictional wear during operation is significantly reduced, improving the mechanical stability of the TENG, and the rolling electrode inside the TENG reduces the friction between the solid surfaces and the direct contact caused by the contact between the rolling electrode and the plate electrode. Electron flow helps to amplify the current, and the present invention using liquid lubricant and direct electron flow can generate instantaneous and root mean square (RMS) power of 0.6 W and 1.26 mW, respectively, at a low speed rotation of 100 rpm. triboelectric with liquid lubricant for current amplification through direct electron flow, capable of producing voltage and current outputs of up to 220 V and 170 mA, respectively, when connected to rectifier circuits sufficient to charge commercial capacitors and lithium-ion batteries, and also to charge commercial capacitors and lithium-ion batteries. Its purpose is to provide a nanogenerator and its operating method.

On the other hand, the technical problems to be achieved in the present invention are not limited to the above-mentioned technical problems, and other technical problems that are not mentioned will become clear to those skilled in the art from the description below. You will be able to understand.

A first object of the present invention is a triboelectric nanogenerator comprising: an inner cylinder having a dielectric; at least one plate electrode surrounding the outer surface of the inner cylinder to be spaced apart by a specific distance; a plurality of rolling electrodes positioned in contact with each other between the plate electrode and the inner cylinder; and a liquid lubricant filled in the space between the plate electrode and the inner cylinder.

And the liquid lubricant may be characterized in that it is a non-polar liquid lubricant.

In addition, it may be characterized in that the dielectric layer is laminated at least once on the outer surface of the inner cylinder.

And the dielectric layer may be characterized in that PTFE.

In addition, it further includes an outer cylinder positioned to be spaced apart from the inner cylinder by a specific distance, the plate electrode is coupled to the inner surface of the outer cylinder, and the rolling electrode is configured in a rod shape and is installed in the front and rear of the outer cylinder, respectively. It may be characterized in that it further comprises; a jig for fixing the longitudinal and radial movement positions of the plurality of rolling electrodes.

In addition, the rolling electrode and the plate electrode may be made of aluminum, and a Teflon wrapping wire may be attached to the plate electrode.

In addition, the inner cylinder, the outer cylinder and the jig may be characterized in that composed of PMMA.

The non-polar liquid lubricant may include at least one of mineral oil and silicone oil.

In addition, by the non-polar liquid lubricant, air breakdown and field emission of the surface charge of the dielectric layer are suppressed, operating friction of the rolling electrode is reduced, and direct electron flow is induced between the rolling electrode and the plate electrode. there is.

A second object of the present invention is a method for operating a triboelectric nanogenerator according to the first object, comprising: rotating an internal cylinder by external input energy and rotating a rolling electrode in conjunction with each other; negatively charged dielectric layer on the outer surface of the inner cylinder; inducing positive charges to a rolling electrode in contact with the dielectric layer and causing polarization; and directly flowing electrons accumulated in the rolling electrode to the plate electrode when the rolling electrode contacts the plate electrode; a triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow It can be achieved as an operating method of.

According to the triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow and its operating method according to an embodiment of the present invention, when the non-polar liquid lubricant is filled in the triboelectric nanogenerator, the long debye of the lubricant Due to the length, it can effectively block air breakdown, and the rolling friction and lubrication can greatly reduce the friction wear of the device, generating high voltage and current outputs of up to 200V and 170mA respectively, which has the effect of charging commercial capacitors and batteries. have

In addition, according to the triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow and its operating method according to an embodiment of the present invention, frictional wear during operation is significantly reduced to improve the mechanical stability of the TENG, and to improve the mechanical stability of the TENG. The rolling electrode of reduces the friction between the solid surfaces and helps to amplify the current through the direct electron flow that occurs when the rolling electrode and the plate electrode come into contact. Capable of generating instantaneous and root mean square (RMS) power of 0.6 W and 1.26 mW, respectively, at low speed rotation, and also capable of up to 220 V and 170 mA voltages and It has the effect of generating a current output.

On the other hand, the effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the present invention, so the present invention is limited only to those described in the drawings. and should not be interpreted.
1 is a perspective view of a triboelectric nanogenerator (LLS-TENG) having a non-polar liquid lubricant for current amplification through direct electron flow according to an embodiment of the present invention;
2 is an exploded perspective view of an LLS-TENG according to an embodiment of the present invention;
3 is a partial cross-sectional view of an LLS-TENG according to an embodiment of the present invention;
4 is a schematic diagram comparing field emission suppression between air (i) and liquid lubricant of LLS-TENG according to an embodiment of the present invention;
5 is a VOC graph for air and liquid lubricant conditions;
6 is an ICC graph for air and liquid lubricant conditions;
7A and 7B show the difference in Debye length (λD) for polar (FIG. 7A) and non-polar (FIG. 7B) liquids.
8a and 8b show VOC and ICC outputs of LLS-TENG in different liquids.
9 is a partial cross-sectional view of an LLS-TENG showing an operating mechanism according to an embodiment of the present invention;
10A and 10B show the VOC (FIG. 10A) and the enlarged VOC output (FIG. 10B) of the LLS-TENG according to an embodiment of the present invention;
11a is a graph of instantaneous voltage, current, and power output of an LLS-TENG according to an embodiment of the present invention;
11B is a graph of RMS voltage, current, and power output of LLS-TENG according to an embodiment of the present invention;
12a and 12b are photographs of an LLS-TENG fabricated according to an embodiment of the present invention (FIG. 12a) and a rectifier circuit (FIG. 12b);
13a and 13b are circuit configurations and photographs of 319 LEDs connected in series (FIG. 13a) and in parallel (FIG. 13b);
14 is a rectified voltage and current of LLS-TENG according to an embodiment of the present invention
15 shows commercial 100, 200 and 300 μF capacitors charged with LLS-TENG according to an embodiment of the present invention;
16 shows a charging graph of a commercial lithium ion battery for LLS-TENG according to an embodiment of the present invention.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

In this specification, when an element is referred to as being on another element, it means that it may be directly formed on the other element or a third element may be interposed therebetween. Also, in the drawings, the thickness of components is exaggerated for effective description of technical content.

Embodiments described in this specification will be described with reference to cross-sectional views and/or plan views, which are ideal exemplary views of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content. Accordingly, the shape of the illustrated drawings may be modified due to manufacturing techniques and/or tolerances. Therefore, embodiments of the present invention are not limited to the specific shape shown, but also include changes in the shape generated according to the manufacturing process. For example, a region shown at right angles may be rounded or have a predetermined curvature. Accordingly, the regions illustrated in the drawings have attributes, and the shapes of the regions illustrated in the drawings are intended to illustrate a specific shape of a region of a device and are not intended to limit the scope of the invention. Although terms such as first and second are used to describe various elements in various embodiments of the present specification, these elements should not be limited by these terms. These terms are only used to distinguish one component from another. Embodiments described and illustrated herein also include complementary embodiments thereof.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. The terms 'comprises' and/or 'comprising' used in the specification do not exclude the presence or addition of one or more other elements.

In describing the specific embodiments below, several specific contents are prepared to more specifically describe the invention and aid understanding. However, readers who have knowledge in this field to the extent that they can understand the present invention can recognize that it can be used without these various specific details. In some cases, it is mentioned in advance that parts that are commonly known in describing the invention and are not greatly related to the invention are not described in order to prevent confusion for no particular reason in explaining the present invention.

Hereinafter, the configuration, function, and operation mechanism of a triboelectric nanogenerator (hereinafter referred to as LLS-TENG 100) having a non-polar liquid lubricant for current amplification through direct electron flow according to an embodiment of the present invention will be described.

First, FIG. 1 shows a perspective view of a triboelectric nanogenerator (LLS-TENG (100)) having a non-polar liquid lubricant for current amplification through direct electron flow according to an embodiment of the present invention, and FIG. 2 is a perspective view of the present invention. It shows an exploded perspective view of the LLS-TENG according to the embodiment of. 3 is a partial cross-sectional view of an LLS-TENG according to an embodiment of the present invention.

4 is a schematic diagram showing a comparison of field emission suppression between air (i) and liquid lubricant (ii) of the LLS-TENG 100 according to an embodiment of the present invention, and FIG. 5 is VOC for air and liquid lubricant conditions. The graph, FIG. 6 shows the ICC graph for air and liquid lubricant conditions.

As shown in FIGS. 1 to 3, the LLS-TENG 100 according to an embodiment of the present invention includes an outer cylinder 1, an inner cylinder 2, a dielectric layer 10, a rolling electrode 20, and a plate electrode. (30), a non-polar liquid lubricant (40), and the like.

The inner cylinder (2), the outer cylinder (1) and the jig (3) may be composed of polymethyl methacrylate (PMMA). In addition, the rolling electrode 20 may be made of aluminum in a rod shape, and the surface of the inner cylinder 2 may be coated with the dielectric layer 10 at least once. This dielectric layer may be composed of polytetrafluoroethylene (PTFE (10)). Also, the inner cylinder 2 itself may be made of PTFE 10.

Four curved plate electrodes 30 are installed on the inner surface of the outer cylinder 1 of PMMA. The plate electrode 30 may be made of aluminum. In addition, the non-polar liquid lubricant 40 according to the embodiment of the present invention is filled in the space between the PTFE 10 layer and the plate electrode 30. That is, the space between the inner cylinder 2 and the outer cylinder 1 is filled.

As the inner cylinder 2 having the dielectric layer 10 rotates through external input energy, the six aluminum rolling electrodes 20 also rotate inside the LLS-TENG 100. Using the rolling electrode 20 and the liquid lubricant 40, the proposed invention provides improved current output and reduced frictional damage.

That is, the occurrence of air breakdown due to the negative surface charge of the dielectric layer 10 (PTFE) is suppressed by the liquid lubricant 40 . In particular, a negative charge induces a positive charge at the top of the rolling electrode 20 and causes polarization at the rolling electrode 20 .

Due to the suppression of air destruction, the LLS-TENG (100) can generate higher electrical output compared to TENGs operating in air. Also, when the rolling electrode 20 contacts the plate electrode 30 , electrons accumulated in the rolling electrode 20 directly flow to the plate electrode 30 . This direct electron flow produces high current output during rotation.

In addition, wear damage is greatly reduced through rolling friction and lubrication.

During air breakdown and field emission, the PTFE 10 surface exhibits a limiting charge density in air. Therefore, according to Paschen's law, field strengths of about 3 kV/mm can cause air breakdown and low field strengths can cause field emission in microscale gaps.

However, when the charged surface is immersed in the liquid lubricant 40, the field strength required for breakdown increases to 20 kV/mm and the minimum field strength required for field emission to occur increases. Therefore, an increase in the surface charge of PTFE (10) can be observed in the liquid condition (FIG. 4). Also, when the device is immersed in lubricant 40, the electric field is reduced. The rolling electrode 20 material is aluminum and the dielectric layer 10 is a PTFE 10 film.

Figure 4 shows the results when each LLS-TENG is filled with air and mineral oil. The permittivities of air and mineral oil are 1 and 2.1, respectively. The surface charge density of the surface of the PTFE 10 is -10 µC m ^-2 and the rolling electrode 20 is set to float. According to the simulation results, an electric field is formed between the rolling electrode 20 and the PTFE 10 film in an air and lubricant environment. The maximum electric field strengths when the device is operating in air and lubricant environments are 5.02 and 2.42 kV mm ^-1 , respectively. According to the permittivity of mineral oil, the electric field strength of mineral oil is lower than that of air. In general, the electric field strength at a point can be described as Equation 1 below.

[Equation 1]

where E is the electric field strength, Q is the charge, ε _r is the relative permittivity, ε ₀ is the vacuum permittivity, and d is the distance dl between the charge and the point. According to Equation 1, the permittivity of the material between the electrode and the dielectric surface affects the electric field strength. When using mineral oil, the electric field strength decreases as the permittivity increases. This interpretation is consistent with the simulation results obtained for the lubricant environment. Nevertheless, as the permittivity increases, the electric field strength in the lubricant 40 decreases but the flux density increases. As a result, the induced positive charge remains unchanged. According to Gauss' law, the electric flux density (D) is related to the electric field strength (E) as:

[Equation 2]

The induced charge is related to the electrical flux of the electrodes. As a result, the positive charge induced at the electrode does not vary with permittivity regardless of the material used (lubricant or air). Nonetheless, air breakdown occurs due to air's high electric field strength, limiting the surface charge.

Due to this reduced surface charge, the electrical flux density associated with the negative charge on the surface of PTFE 10 is reduced compared to that of mineral oil. Therefore, there is a significant difference in the electrical output of the LLS-TENG (100) in the air and lubricant (40) environment.

Figure 5 shows the open circuit voltage (VOC) output of the LLS-TENG during operation. As shown in Figure 5, the maximum VOC when the device is operating in an ambient environment is about 28V. However, it can be seen that the maximum VOC increases to 200V when the generator is filled with liquid lubricant (40).

In addition, it can be seen that the closed circuit current (ICC) output of the LLS-TENG 100 of the lubricant (85mA) is significantly higher than that of the air (5mA) as shown in FIG. 6 . Although the peak ICC output has a smaller electrical peak than VOC, as can be seen in the enlarged output plot described later, ICC output in the range of 5 to 10 mA is continuously generated when the LSS-TENG 100 rotates. This increased electrical output shows that the introduction of liquid lubricant 40 improves the mechanical life and electrical performance of the TENG.

7a and 7b show the difference in Debye length (λD) for polar (FIG. 7a) and non-polar (FIG. 7b) liquids. 8a and 8b show the VOC and ICC outputs of the LLS-TENG in different liquids.

In the case of TENGs using liquid as a triboelectric material, the electric double layer (EDL) appears to have a significant effect on the electrical output. When a liquid contacts a solid surface with an electric charge, the liquid molecules form two layers parallel to the solid surface.

The length of the EDL is defined as the Debye length (λD) and the electrostatic charge on the solid surface is screened for each Debye length. That is, when a solid material with a surface charge is immersed in a liquid, the surface charge is blocked by the charge carriers of the liquid, such as electrons, ions, or molecules. As can be seen in Figures 7a and 7b, the LLS-TENG 100 includes a cylinder of PTFE 10 exhibiting a negative surface charge and a rolling electrode 20 in contact with the surface. When the device is immersed in a polar liquid, molecules of the polar liquid block the electrostatic field of the negative surface charge at the PTFE(10) surface (Fig. 7a). This screening greatly limits the positive charge induced on the rolling electrode 20 .

However, since non-polar liquids such as mineral oil and silicone oil have a larger Debye length than polar liquids (FIG. 7b), a higher negative charge of PTFE 10 is induced on rolling electrode 20 through polarization of the electrode. The geometrically larger Debye length of the non-polar liquid corresponds to a higher surface area due to the negative surface charge of PTFE 10 . Moreover, charge screening specific to polar liquids and non-polar liquids occurs at the surface of the rolling electrode 20 .

Figures 8a and 8b show the VOC and ICC outputs when LLS-TENG was filled with mineral oil, silicone oil, castor oil, water and ethyl alcohol, respectively. Mineral oil/silicone oil are typical non-polar liquids, water/ethyl alcohol are polar liquids.

The highest electrical output was produced when filled with mineral oil. Moreover, when the device was filled with water and ethyl alcohol, the electrical output generated was almost zero and could not be measured. In general, castor oil is more polar than other oils due to the presence of hydroxyl groups in ricinoleic acid. Therefore, in the case of castor oil, the electrical output was lower than in the case of other non-polar liquids. The electrical output result depends on the debye length of the liquid. In general, the via length of polar liquids is relatively small (the Debye length of water is only 10 to 20 nm, and that of ethanol is about 38 nm). In contrast, the Debye length of non-polar liquids is greater than 1 μm, much larger than that of polar liquids.

9 is a partial cross-sectional view of an LLS-TENG showing an operating mechanism according to an embodiment of the present invention. 10A and 10B show the VOC (FIG. 10A) and the enlarged VOC output (FIG. 10B) of the LLS-TENG according to an embodiment of the present invention, and FIG. 11A is the instantaneous voltage of the LLS-TENG according to the embodiment of the present invention. , current, and power output graphs are shown. In addition, FIG. 11B shows a graph of RMS voltage, current, and power output of the LLS-TENG according to an embodiment of the present invention.

The working mechanism of the LLS-TENG 100 to generate output includes three major steps, as shown in FIG.

First, the negative charge on the surface layer of PTFE (10) induces a positive charge on the rolling electrode (20). Naturally, the negative charge is separated from the positive charge by the PTFE (10) surface and accumulates on the opposite side. As the rolling electrode 20 approaches the plate electrode 30, a direct flow of electrons occurs as the two electrodes come into contact with each other.

The electrical output of the LLS-TENG 100 is amplified due to this flow. As described above, the liquid lubricant 40 inhibits air breakdown to increase the surface charge of the PTFE 10 and increase its mechanical life.

The VOC output measured when the PTFE (10) cylinder of the LLS-TENG (100) operates at 100 rpm is shown in Figs. 10a and 10b. Attached electrodes are connected as in a free-standing TENG. As shown in FIG. 10A, the LLS-TENG 100 generates a peak voltage output in the range of 100 to 200V. An enlarged voltage output is shown in FIG. 10B. It can be seen that a unique shape peak can be observed because direct electron flow occurs due to the contact between the rolling electrode 20 and the plate electrode 30.

Examining voltage, current, and power output according to various external load resistances to clarify electrical output characteristics, FIG. At this time, the input rotation is 100 rpm. As the external load resistance increases from 10Ω to 1kΩ, the instantaneous voltage output does not change significantly. However, as the external resistance increases from 1kΩ to 1MΩ, the voltage output increases. Also, as the external resistance increases from 1MΩ to 100MΩ, the voltage output gradually decreases. The highest current output occurs at 10Ω and the output continuously decreases as the external resistance is further increased.

According to this result, the LLS-TENG 100 can generate about 0.6W of instantaneous power when the external resistance is 1MΩ. Continuous electrical output is a key factor for applying TENGs to existing electronic devices. In an embodiment of the present invention RMS was taken into account to determine the average power produced by the LLS-TENG 100. RMS voltage (VRMS) and RMS current (IRMS) are calculated as:

[Equation 3]

Here, V(t) and I(t) represent voltage and current over time, respectively. Voltage and current results are measured from T ₁ to T ₂ . RMS power (WRMS) is determined by multiplying VRMS and IRMS.

The RMS results obtained when the LLS-TENG 100 was rotated at 100 rpm are shown in FIG. 11B. VRMS does not change significantly when the external load resistance increases from 10Ω to 1MΩ. However, VRMS increases when the external load resistance increases from 10 MΩ to 1 GΩ. The highest VRMS is 7.96V when the external load resistance is 1GΩ.

Conversely, IRMS decreases as the external load resistance increases. The highest IRMS is 1.49mA when the external load resistance is 10Ω. WRMS decreases as the external load resistance increases from 1 to 100MΩ, the resistance increases to 1GΩ. The highest WRMS is 1.73mW with an external resistance of 100MΩ. The instantaneous and RMS power results show that the LLS-TENG (100) can be used as an energy source in practical applications.

12a and 12b are photographs of an LLS-TENG (FIG. 12a) and a rectifier circuit (FIG. 12b) manufactured according to an embodiment of the present invention, and FIGS. 13a and 13b are in series (FIG. 13a) and in parallel (FIG. 13b). 14 is a graph of rectified voltage and current of LLS-TENG according to an embodiment of the present invention, FIG. 15 is a commercial 100, 200 and 300 μF capacitor charging LLS-TENG according to an embodiment of the present invention 16 shows a charging graph of a commercial lithium ion battery for LLS-TENG according to an embodiment of the present invention.

In the manufacture of the LLS-TENG according to the embodiment of the present invention, the LLS-TENG (100) is an aluminum rolling electrode that rolls between the outer cylinder (1), the inner cylinder (2), and the outer cylinder (1) and the inner cylinder (2). (20), and a jig (3) for fixing the aluminum rolling electrode (20).

The outer cylinder (1) made of PMMA has a height and diameter of 100 mm and 70 mm, respectively. Four plate electrodes 30 are attached to the inner surface of the outer cylinder 1. Four pieces of 100 mm × 40 mm commercially available aluminum tapes (Duksung Hitech Co., Ltd.) with a thickness of 0.05 mm were used as the plate electrodes 30. In addition, a commercial Teflon wrapping wire (AWG 24) is attached to the plate electrode 30.

In addition, the inner cylinder (2) made of PMMA has a height and diameter of 100 mm and 40 mm respectively. The outer surface of the inner cylinder (2) is covered with several layers of PTFE (10) tape with a thickness of 0.13 mm. Six aluminum rolling electrodes 20 are provided between the inner cylinder 2 and the outer cylinder 1. The jig 3 is used to ensure a constant distance between the aluminum rolling electrodes 20.

In the experimental example of the present invention, voltage and current are measured using a mixed domain oscilloscope (MDO 3015, Tektronix Co.), a current probe (TCP0030A, Tektronix Co.) and a digital multimeter (Fluke 289, FLUKE Co.) It became. Magnified pictures were obtained using an optical microscope (BX53M, Olympus).

As shown in FIG. 12A, it can be seen that the LLS-TENG 100 has four plate electrodes 30 attached to the inner surface of the PMMA outer cylinder 1. Each plate electrode 30 is connected to the middle region of two fast switching diodes, as shown in Fig. 12b for output rectification.

With its high electrical output, the LLS-TENG (100) can power 319 LEDs connected in series and parallel. 13a and 13b show the circuit configuration of 319 LEDs connected in series and parallel, respectively, and the corresponding pictures of the LEDs turned on when the LLS-TENG 100 operates.

14 shows the rectified voltage and current output of the LLS-TENG. Power was measured at 100 rpm of input rotation. It can be seen that the peak voltage and current outputs are 220V and 171mA respectively. The LLS-TENG (100) can generate high current output, but energy storage must be ensured for use in commercial products.

15 shows graphs of 100, 200 and 300 μF capacitors charged using the LLS-TENG 100. In particular, it can be seen that the LLS-TENG 100 can charge 100, 200, and 300 μF capacitors to 3.28, 1.72, and 1.04V within 200 seconds, respectively.

In addition, the LLS-TENG 100 can charge a commercial lithium ion battery (LIB) through a battery charging circuit including a capacitor. The battery charging circuit stores charge from the device into a capacitor and transfers this charge to the battery for stable charging. Figure 16 shows the charge plot of a 3V, 2mAh LIB battery connected to LLS-TENG(100). It can be seen that the battery charges from 2.737V to 2.763V in 4 hours. This result suggests that the LLS-TENG 100 can be used as an auxiliary power source for commercial battery charging.

Examples of the present invention demonstrate the use of TENGs filled with liquid lubricant 40 to improve the electrical and mechanical properties of conventional TENGs.

The surface charge of PTFE 10 can be enhanced through suppression of air breakdown and field emission by liquid lubricant 40 . Non-polar liquid lubricants 40 such as mineral oil and silicone oil can enhance the electrical output of the TENG due to its long Debye length.

In addition, the rolling electrode 20 of the LLS-TENG 100 can reduce friction during operation and induce a direct flow of electrons between the electrodes, thereby increasing electrical output. At an input rotation of 100 rpm, the LLS-TENG 100 can generate up to 220 V and 171 mA of VOC and ICC, respectively. The instantaneous and RMS powers of the LLS-TENG 100 during operation are 0.6 W and 1.73 mW, respectively. With such a high current output, it was found that the LLS-TENG (100) could successfully power 319 LEDs connected in series and parallel.

In addition, LLS-TENG 100 can charge commercial capacitors and LIBs. Therefore, it was demonstrated that the mechanism according to the embodiment of the present invention can expand the applicability of TENG by overcoming electrical and mechanical limitations and promoting the use of LLS-TENG (100) as an auxiliary power source.

In addition, the device and method described above are not limited to the configuration and method of the above-described embodiments, but all or part of each embodiment is selectively combined so that various modifications can be made. may be configured.

1: External cylinder
2: Inner cylinder
3: jig
10: dielectric layer, PTFE
20: rolling electrode
30: plate electrode
40: non-polar liquid lubricant
100: triboelectric nanogenerator with liquid lubricant for current amplification through direct electron flow (LLS-TENG)

Claims (10)

In the triboelectric nanogenerator,
an inner cylinder having a dielectric layer;
at least one plate electrode surrounding the outer surface of the inner cylinder to be spaced apart by a specific distance;
a plurality of rolling electrodes positioned in contact with each other between the plate electrode and the inner cylinder; and
A triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, characterized in that it comprises a liquid lubricant filled in the space between the plate electrode and the inner cylinder.
According to claim 1,
The triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, characterized in that the liquid lubricant is a non-polar liquid lubricant.
According to claim 2,
A triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, characterized in that the dielectric layer is laminated at least once on the outer surface of the inner cylinder.
According to claim 3,
The dielectric layer is a triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, characterized in that PTFE.
According to claim 2,
Further comprising an outer cylinder spaced apart from the inner cylinder by a specific distance, wherein the plate electrode is coupled to an inner surface of the outer cylinder,
The rolling electrode is configured in a rod shape, and is installed at the front and rear of the outer cylinder, respectively, to fix the longitudinal and radial movement positions of the plurality of rolling electrodes; direct electron flow characterized in that it further comprises Triboelectric nanogenerator with liquid lubricant for current amplification through
According to claim 1,
The rolling electrode and the plate electrode are made of aluminum, and a triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, characterized in that a Teflon wrapping wire is attached to the plate electrode.
According to claim 5,
The triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, wherein the inner cylinder, the outer cylinder, and the jig are composed of PMMA.
According to claim 2,
The triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow, characterized in that the non-polar liquid lubricant includes at least one of mineral oil and silicone oil.
According to claim 2,
Air breakdown and field emission of the surface charge of the dielectric layer are suppressed by the non-polar liquid lubricant, the operating friction of the rolling electrode is reduced, and direct electron flow is induced between the rolling electrode and the plate electrode. Triboelectric nanogenerator with liquid lubricant for current amplification through flow.
In the method of operating the triboelectric nanogenerator according to any one of claims 1 to 9,
Rotating the inner cylinder by external input energy and rotating the rolling electrode in conjunction with each other;
negatively charged dielectric layer on the outer surface of the inner cylinder;
inducing positive charges to a rolling electrode in contact with the dielectric layer and causing polarization; and
When the rolling electrode contacts the plate electrode, the electrons accumulated in the rolling electrode directly flow to the plate electrode; of the triboelectric nanogenerator having a liquid lubricant for current amplification through direct electron flow How it works.

Images