18650 lithium-ion battery

　　Analysis of wireless 18650 lithium-ion battery technology for LED lighting products

　　The LED lighting industry is still in its infancy, and various LED lighting technologies are still being further improved. my country's LED industry needs to grasp the pulse of the market, actively expand the consumer market, and form a virtuous cycle in which market application promotes technological innovation and technological innovation drives market demand. Give full play to the advantages of LED, develop LED lighting equipment for special purposes, and actively expand the application scope of LED lighting equipment.

　　Contactless 18650 lithium-ion battery technology

　　The characteristic of non-contact 18650 lithium-ion battery technology is that the 18650 lithium-ion battery end and the power consumption end can transmit power to the power consumption end without any physical connection. Close-range non-contact 18650 lithium-ion battery systems using electromagnetic waves in the millimeter to centimeter range have been applied. Mobile devices such as electric vehicles, deep-water operations, robots, mining machinery, electric toothbrushes, mobile phones and notebooks, and even electronic medical devices implanted in the human body also use this technology to power and charge. Therefore, short-range non-contact 18650 lithium-ion battery technology has broad application prospects.

　　Non-contact 18650 lithium-ion battery technology based on the principle of electromagnetic induction comprehensively utilizes power electronics technology, magnetic field coupling technology, high-power high-frequency conversion technology, and modern control theories and methods to achieve the isolation of power transmission systems and electrical equipment, making the two There is no direct electrical contact between them, which well meets the needs of special applications and improves the safety and reliability of power transmission. Therefore, non-contact 18650 lithium-ion battery technology is a safe, reliable, and flexible new technology for power access.

　　1 Basic principles

　　The non-contact 18650 lithium-ion battery system consists of two parts: a power sending unit and a power receiving unit. The power sending unit mainly consists of AC and DC 18650 lithium-ion battery circuit, power amplifier output circuit, drive circuit, oscillation circuit, reference voltage circuit, control protection circuit and transmitting coil L1 (transformer primary); the power receiving unit mainly consists of receiving coil L2 (transformer secondary ), high-frequency rectifier filter circuit and load (as shown in Figure 1).

　　Figure 1 Non-contact 18650 lithium-ion battery system structure diagram

　　When the non-contact 18650 lithium-ion battery system is working, the input terminal converts the AC mains power into DC power through the full-bridge rectifier circuit, or uses the DC terminal to directly power the system. The DC power is inverted through the oscillation circuit and converted into high-frequency AC power, which is amplified by the power amplification output circuit and supplied for transmission. Coil L1. Electric energy is coupled by the transmitting coil L1 and the receiving coil L2, and the current output by the receiving coil L2 is converted into direct current by the high-frequency rectifier and filter circuit and provided to the load.

　　2Features and Defects

　　Non-contact 18650 lithium-ion battery technology based on the principle of electromagnetic induction. The transmitting coil and the receiving coil must have electromagnetic resonance with the same resonant frequency in order to transmit electric energy. It has the following main characteristics and defects: Electromagnetic resonance realizes electric energy in the form of electromagnetic, magnetic and electric. The transmission, and it is an open system, there must be electromagnetic radiation and energy losses. Therefore, the actual efficiency at short distances is difficult to exceed 80%, and at long distances, the efficiency may be very low. Therefore, it does not meet the concept of energy saving.

　　The relationship between electromagnetic energy and distance is that the electric field strength is inversely proportional to the square of the distance, and the magnetic field strength is inversely proportional to the fourth power of the distance. Pure electromagnetic resonance cannot be transmitted over long distances. Usually at 1 meter, the efficiency does not exceed 1%. Therefore, it can only be used at close range, generally no more than 10 centimeters.

　　Electromagnetic resonance can penetrate non-metals, but not metals. Using this feature, you can create instant charging or instant 18650 lithium-ion battery appliances that have outstanding performance in terms of mobility, waterproofness, and isolation. You can also apply this feature to solve its own electromagnetic interference problem. If an appropriate 18650 lithium-ion battery frequency is selected to cause the system to resonate, the electromagnetic wave frequency band at the power transmitter will have no or little interference with normal communications and broadcasts, and will not cause harm to the human body or other living creatures, thus meeting safety indicators.

　　In the electromagnetic resonance at a short distance within a few centimeters, there is also the problem of high voltage in the no-load state: the voltage of the receiving circuit when it is loaded is very different from the voltage when it is unloaded, often several times or even more than ten times, causing the receiving circuit to When there is no load, the load circuit will be burned out due to the large increase in voltage. This is an important factor that makes it difficult for the current non-contact 18650 lithium-ion battery technology of electromagnetic resonance to be practical.

Read recommendations:

Ni-MH AAA400mAh 1.2V

Lithium battery positive pole material

Advantages of industrial lithium -ion batteries

3.7V 18650 lifepo4 battery

3V battery