Can a friction generator generate electricity to reach the dam?
The triboelectric effect is one of the most common phenomena in nature. It is a phenomenon in which two different materials are frictionally rubbed to contact the surface. The two sheets that are in contact with each other are not charged on the surface, but after the contact, the properties are different due to different materials, one is easy to lose electrons, and one is easy to get electrons, thereby causing the two materials to contact one another. Positively charged, one side is negatively charged. This is the frictional electrification that we generally know. Although this phenomenon is common, it has not been effectively utilized as a power source except for being used to form a high-voltage electric field in electrical experiments.
In late March, reports on “friction generators” caused widespread concern. The news was selected from January 2012. The research team of Wang Zhonglin, the chief scientist of the Beijing Institute of Nano Energy and Systems, Chinese Academy of Sciences, designed a series of friction generators.
After the two sheets are charged by the contact friction surface, the surfaces of the two sheets are separated. Since the objects have a tendency to maintain electrical neutrality, the two sheets are connected to the external circuit through the electrode layer, and the electrons pass through the external circuit. Flowing between the two electrode layers to form a current - according to this principle, the generator can convert the mechanical energy of breeze, water flow, and even human motion in nature into electrical energy. This new type of friction generator is also cost-effective while ensuring power generation efficiency.
Friction generator can be combined with conventional generators to generate electricity
Friction generators are different from traditional "electromagnetic induction generators" and "friction starters". The core of friction generators lies in two important ideas, one is the coupling of frictional electrification and electrostatic induction, and the other is thin layer. Electrode design. The reporter learned that because of the use of film materials with a micron-thickness thickness, the entire device can be soft or even transparent.
Although the initial output current and power of the friction generator were not ideal, with the efforts of the Wang Zhonglin team, after two years, the problem has been successfully overcome. The researchers found that during the sliding process of the two working parts of the friction generator, the amount of charge transfer between the electrodes can be greatly improved by the orderly patterning of the material surface, and it is quasi-linear with the pattern density.
Therefore, they designed a patterned array structure that produced a qualitative leap in the output power of the friction generator. The latest friction power generation unit consists of a planarized circular stator and a rotor. It uses a surface-patterned friction layer and electrode layer to achieve an average output power of 1.5W through a rotary contact drive design, achieving up to 24%. - 50% energy conversion.
Compared with the traditional generator, the output of the friction generator has the characteristics of high voltage and low current, which can form a complementary power generation mode with the low voltage and high current of the conventional generator.
At the same time, because the friction generator uses a light and inexpensive organic film, its power generation per unit volume is 30 to 50 times that of a conventional generator, and the power generation per unit mass is 30 to 40 times that of a conventional generator. It has a very large advantage in output power density. At present, the Wang Zhonglin team is developing and improving friction generators in terms of durability. The existing friction generators still have no attenuation in the use of 1 million rotations.
What is the difference between a friction generator and a manual power generator?
At the Beijing Institute of Nano-Energy and Systems, Chinese Academy of Sciences, Wang Zhonglin showed the reporter the power generation effect of the friction generator: the two pieces connected together, gently pinching the surface to make contact, after releasing the hand, the lights connected to the terminal are successively Light up. This way of converting mechanical energy into electrical energy is not the first time it has appeared.
A similar push-type flashlight also converts mechanical energy into electrical energy, which is different from a friction generator.
In principle, the power generation process of the push-type flashlight is based on the traditional electromagnetic induction power generation principle. The mechanical energy is provided by the pressing of the hand, and the gear inside the flashlight is driven to rotate, thereby driving the coil to perform the movement of the cutting magnetic line to generate the current. Such a power generating device must have a built-in magnet to form a magnetic field, resulting in a relatively large volume and weight, a complicated internal structure, and a low output power, which is a "small electrical appliance" with a small power. The friction generator uses a light and thin plastic film, which is compact and simple in structure, and the output current is increased to 3 mA through the patterned design of the friction surface, so that it can realize not only "small appliances" such as mobile phones. Real-time power supply, and it is easy to form an array through multiple sets of friction generators to achieve large-scale energy supply.
By combining generators and power management circuits, the researchers have further developed a complete small power supply system. The system features functions such as impedance reduction, rectification, energy storage, and voltage regulation. It provides a constant-voltage stable DC output, providing real-time power or direct charging for a variety of common electronic products, including mobile phones. Current output power densities are up to 500 watts per square meter.
