Disasters often occur when people are not paying attention. In addition to having a good sense of prevention, if there is a convenient and effective rescue equipment, it is likely to help you escape from danger.

In the afternoon of March 18, 2014, Beijing Institute of Nano-Energy and Systems, Chinese Academy of Sciences, held a demonstration of new energy technologies for frictional power generation. Wang Zhonglin, a member of the Nano Energy Institute, presented the latest research results of friction electric generators. It also conducted on-site operations to experience a new energy supply model that can “generate electricity with every move”.

Academician Wang Zhonglin first introduced the basic principle of the triboelectric generator, and showed the working status of several triboelectric generators through video. Afterwards, Academician Wang Zhonglin and his team’s researchers demonstrated to reporters in the laboratory including rotary DC friction generators, brake power generation simulators, self-driven wireless touch alarms, flexible transparent friction generators, and disc wide-band friction generators. ,Foot-type friction generators, tidal energy collection devices, etc., including 20 on-site power generation operation of friction power generation devices. The triboelectric generators have demonstrated their ability to efficiently collect various mechanical energy such as air flow, water body flow, and human activity, as well as their enormous application prospects in terms of green energy supply and self-powered sensing.

Friction of electric generators will help disaster relief

The power source of the triboelectric generator can be a large energy source such as wind power, water power, and ocean waves that have been known, and it can also be people's walking, body shaking, hand touch, falling raindrops, etc. that have never been noticed by people. The environmental random energy can be the waste of the wheels, the roar of the machine, etc., which are wasted by people, and are even unpleasant. Triboelectric generators achieve effective collection of mechanical energy by being attached to objects that generate these powers. Such a wide range of application is mainly due to the good compatibility of its structure with the main body of the movement, and this compatibility also makes it possible to directly supply power to portable and wearable devices through human activities to fundamentally solve the functions of portable devices. More and more, the contradiction of batteries is becoming more and more insufficient.

"In the future, when people encounter disasters such as plane crashes and earthquakes, they can use their own power generation equipment to transmit rescue signals." Academician Wang Zhonglin demonstrated on-the-spot glove friction electricity generation technology. This technology may extend to the arm when walking, even skirts. Pendulum friction. When faced with a major disaster, trapped persons can provide search and rescue personnel with important location information through self-generation.

Triboelectric generator will fully upgrade wearable equipment

The study found that the electrical signal output of the triboelectric generator has a significant correlation with the nature of the power source, which makes the triboelectric generator not only can be used as a power source, but also can be used as a sensor to reflect the motion information of the object. Feeling the terminal does not need power source, can drive through the activity of the test object itself, realize the self-driving active sensing. The technology will have a very broad application prospect in the fields of human-computer interaction, intelligent sensing and smart skin.

The cost of the friction generator is very low, the main components are composed of organic materials and common metals, and the amount is very small, which is very suitable for large-scale industrialization promotion. Its output performance can be controlled and improved by simple material replacement or nano-coating on the surface of the material. It can also be chemically modified on its surface to achieve a richer functionality. This has added a lot of basic and applied research opportunities to the chemistry and materials fields, and may even lead to some new research directions, which will drive the rapid development of emerging industries.

Friction generators have only been in existence for more than two years since they were first introduced, but in the past two years, they have demonstrated to people through the diversification of their power generation modes, the height-adjustability of their structures, and the continuous leaps in output performance. The unlimited potential of its future applications has aroused great interest in academia and industry. We can imagine that when carrying a mobile phone no longer needs a battery, when the wristband can feel healthy, the smart life in science fiction films will be far away from us?

Friction hair application

1. Push/slide friction generator

The principle of the push/slide frictional generator is based on the contact/sliding friction electrification. Two opposite frictional materials are used as the friction surface. By pressing or sliding, the surfaces of the two materials are opposite in polarity. The charge. The triboelectric charge causes a potential difference, which drives the electrons to reciprocate in an external circuit, directly supplying power to the electronic device or charging the energy storage element.

2. Vibration type friction generator

The vibration type frictional generator is based on the principles of frictional electrification and electrostatic induction, and connects two friction materials through springs to achieve contact and separation of materials under the action of environmental vibration, thereby generating a pulsed current output. Vibrating friction generators can capture the vibrational energy of buildings, vehicles, and even living organisms, and continue to provide energy sources for low-power, portable electronic devices or implantable medical devices.

3. Rotary DC friction generator

The principle of the rotary DC friction generator is based on the phenomenon of friction electrification and electrostatic induction. Two rotary disks and two pairs of carbon fiber flexible brushes are used to generate continuous output direct current by sliding friction and electrode switching driven by rotating mechanical energy. Rotary DC friction generators can be used as a constant current source, directly and continuously for powering electronic components or charging energy storage components.

4. Self-powered beam conditioner

The self-energizing beam conditioner consists of a friction generator and a piezoelectric fiber sheet. The high voltage output by the two frictionally opposite materials generates friction to drive the bending deformation of the piezoelectric sheet to achieve the adjustment of the incident light beam. The beam regulator does not need high voltage power supply, and the collected energy can be directly used to drive the piezoelectric sheet under the action of external force to realize the remote control of the macroscopic mechanical motion to the micro actuation. The utility model has the characteristics of high efficiency and energy saving, and is suitable for the self-driven system. .

5. Braking power simulation device

The brake pad simulation device utilizes the principle of electrostatic induction to collect the electric energy generated by the relative movement between the brake pad and the wheel during the daily rotation of the wheel to provide electric energy for the on-board electronic devices, lamps, etc., and to obtain up to several watts of electric energy output at the moment of braking.

6. Self-driven wireless touch alarm

The self-driven wireless touch alarm combines the friction generator and the power regulation circuit to reduce the output voltage of the generator and increase the total amount of output charge through series and parallel switching of the capacitor array. At the same time, as the generator discharge time is shortened, its output current and power can be greatly improved. Therefore, the electric signal generated by the generator after pressing can directly excite the infrared signal through the infrared emission tube, which lays the foundation for the self-driven sensing technology.

7. Textile friction power gloves

Textile friction generator uses nylon, polyester and other common textiles as the friction surface, and uses conductive carbon fiber cloth or silver fiber cloth as the electrode material. A single friction can generate hundreds or even thousands of volts, and the power generation effect is remarkable. This type of friction generator is flexible and can be used as a clothing fabric in the future to collect the energy generated by people's daily activities and power various portable electronic devices. The power generation gloves made using the friction generator can be used as physics experiment equipment, magic props, toys and other fields in primary and secondary schools.

8. Self-powered glow clap

Glow claps are commonly used products for entertainment events such as parties and concerts, but currently, the luminescent clap devices on the market are powered by batteries. This is not only a waste of resources, but also a potential threat to the environment. The luminous clap device adopts a friction generator instead of a battery to supply power to the LED, which is not only low in cost, but also energy-saving and environment-friendly, and more interesting, which is favorable for popularizing the application of the friction generator in the toy field and has a broad market prospect.

9. Flexible transparent friction generator

The flexible transparent friction generator uses a fully transparent polymer substrate and electrodes, and the polymer film surface is microfabricated to make various regular microarray structures, thereby enhancing the friction effect and improving the output efficiency of the nanogenerator, 3cm. The ×3cm flexible device can light up more than 50 LEDs simultaneously. Nano-generators with both flexibility and transparency have broad application prospects in fields such as optical devices, electronic display devices, and personal electronic devices.

10. Dish Wide Frequency Friction Generator

The principle of the dish-type wide-frequency friction generator is based on the sliding frictional electrification effect. Two kinds of film materials with different friction sequence are respectively fixed on two different-sized disks to realize full contact relative sliding and pass through three springs. After each relative sliding, the friction material on both disks can be restored to the initial state. Disc-type wide-frequency friction generators can be used to collect mechanical energy at various vibration frequencies for powering electronic devices or charging energy storage components.

11. Foot-type friction generator

The principle of the foot-operated triboelectric generator is based on the push-type frictional electrification effect, sandwich-parallel structure, which allows the output current to double in the spatial range. The middle wave type sandwich can not only be used as the friction surface of the parallel frictional generator, but also can be restored to the original position after accepting external stress, so as to realize the continuous operation of the device. Foot-operated triboelectric generators can be used to collect the energy generated by a person pressing the ground while walking to drive electronic devices or energy storage.

12. Tidal energy collection device

The ocean accounts for about 71% of the Earth's area, and its existence of a large amount of energy remains to be exploited by us. As a natural phenomenon in the ocean, tides cannot be used for a long time because of the existence of energy and cause waste of energy. The tidal energy gathering device relies on the slap of the waves to promote the contact separation of the frictional surfaces, convert mechanical energy into electrical energy, and achieve energy collection. This device has a low cost, is conducive to industrial production and has a wide application prospect.

13. Self-powered electronic float

Electronic floatation plays an important role in marine science and environmental monitoring. However, electronic floats on the market today are powered by batteries, causing a waste of energy. The electronic float is separated by the contact of a friction generator and generates electric energy to power the LED lamp. And can be used as a vibration and position sensor to accurately determine the size of the waves, make full use of marine mechanical energy, and has broad application prospects.

14. Single electrode friction power generation ball

Based on the phenomenon of frictional electrification and electrostatic induction, a three-dimensional spherical frictional generator can effectively collect the vibration energy of the entire surrounding space. The system adopts the single-electrode mode. Under the two forms of contact separation and sliding friction, the metal electrode loses electrons and thus has a positive charge, resulting in a potential difference with the ground and driving the flow of electrons in the external circuit.

15. Carpet status device

The carpet positioning device uses a single electrode mode. The electric charge carried by the pedestrian's shoe induces the opposite polarity of charge through the electrostatic induction phenomenon. There is a potential difference between these charges and ground, which drives the flow of electrons in the external circuit. The carpet positioning device can not only accurately determine the specific position of the pedestrian, but also can collect the mechanical energy of walking.

16. Wind friction power generation device

The wind power generation device is a device that converts wind energy into electrical energy. Based on the combination of contact separation type and sliding type friction, a plurality of friction plates are driven continuously by the rotation of the wind to drive the rotor to generate high-frequency output of alternating current through the rectification. The bridge is directly and continuously used to power the electronic device or charge the energy storage element.

17. High-power friction generator

The high-power frictional generator is composed of a planarized circular stator and a rotor. The surfaces of the materials that are in contact with each other are composed of a circle of tiny sectors that are radially enclosed. In the process of mutual sliding, the amount of charge transfer between the electrodes can be greatly improved by orderly patterning of the material surface, resulting in a qualitative leap in the output power of the friction generator. The generator's highest average output power is 1.5 watts and its power density is as high as 19mW/cm2, which corresponds to an energy conversion efficiency of 24%.

18. Array type friction generator

The principle of arrayed nanogenerators is a self-driven dynamic/static pressure testing and imaging system based on a friction generator. Friction generators are arranged in an array type, and after any pixel is stressed, voltage and current will be output in corresponding positions. The voltage output is used to characterize the static pressure change of the device, and the current output is used to characterize the dynamic pressure changes experienced by the device. . Secondly, the voltage output is linearly related to the pressure, so the self-actuated pressure test and imaging system also has a high sensitivity, fast response pressure test function.

19. Acoustic wave sensor device

The acoustic wave sensor adopts a double-layered structure of an organic polymer film and a metal electrode. The surface of the polymer film is micro-fabricated to form various regular micro-array structures, thereby enhancing the friction effect and thereby increasing the sensitivity of the sensor. The film is forced to vibrate under the action of sound waves, generates friction with metal electrodes, and generates inductive charges, thereby outputting electrical signals. This sensor can be used in atmospheric and liquid environments for sound recording and sound source localization.

20. Water droplet generator

The device can effectively collect and store the electrostatic energy generated by friction with the air during the falling process of the water droplets (raindrops). It has the advantages of simple structure, low cost, no toxicity, no pollution and the like, and is an effective way to collect a wide range of natural energy sources.