Nowadays, the mobile power supply on the market is almost dazzling, but the quality is uneven, and most of them are fake and shoddy products. From time to time, the accident of the fire/explosion of the mobile power supply is worrying. How to correctly select the mobile power supply? System home Xiaobian for your support: First, the mobile power supply constitutes a mobile power supply that is simply composed of a casing, a battery, and a circuit board. The battery core is the core of the mobile power supply. Now move the power supply or use the finished 18650 battery as the battery, or use a separate battery. The quality of the battery determines the quality of the mobile power supply. The circuit board is mainly to control the step-up and step-down circuit, to do various monitoring and control, and to have multiple chips. The outer casing protects against heat dissipation. Second, the battery detailed lithium battery actually has a battery, our mobile phone battery is also open and there are batteries. The quality of the battery determines the quality of the battery and also determines the quality of the mobile power supply. The classification of lithium battery cells is complex. Generally speaking, it can be divided into: the battery is positive, negative, composed of electrolyte, and the electrolyte type is relatively small. One type is traditional electrolyte. We call it lithium ion battery, no other name, and one type is organic. The polymer is an electrolyte, but the organic polymer is no longer a liquid. We call it a lithium polymer battery or a lithium ion polymer battery. This is two major categories. For mobile power or batteries, the capacity of lithium polymer batteries is higher, and because there is no liquid, it will not explode at high temperature, and the safety is relatively better. It is the first choice for consumers, but the price comparison of lithium polymer batteries High, cost-effective. Under the two categories, according to the difference of the battery positive material (the negative material is mostly graphite), it is divided into lithium cobalt oxide lithium ion (polymer, not added later, the same below) battery, lithium manganese oxide lithium ion battery, Three raw materials lithium ion battery, lithium iron phosphate lithium ion battery. Here, the number of lithium cobalt oxide cycles is relatively small, and the safety is relatively poor, but it is relatively cheap and the most used, most of which are on the market. The performance of the ternary material is better, except for the peak current overload, other indicators are good, but expensive, less used. Lithium manganate has good safety and overload is good, but the capacity is not good, the life is not good, and it is used less. Lithium iron phosphate has the best life expectancy and large overload, but the capacity is not good and the price is expensive. The mobile power supply is basically useless. Therefore, most of the batteries used in mobile power supplies that we can buy today are lithium cobalt oxide lithium ion batteries or lithium cobalt oxide polymer batteries. From the manufacturers, Japan has Sony, Sanyo, South Korea has LG, China's powerful God, BAK, BYD, are big manufacturers, quality is guaranteed. However, you can't see the battery of the mobile power supply. There are often manufacturers who use small batteries or even workshops. The batteries have requirements for the process when they are processed. Some small factories or workshops will not have high standards. Danger and performance are difficult to guarantee. The power of 100 cycles has dropped dramatically. Third, the circuit details of the mobile power control circuit mainly includes such parts 1, lithium battery management chip: monitor the entire charging process, the implementation of lithium battery pre-charge, constant current, constant voltage three-stage charging. 2. MCU: The intelligent control system on the PCB prevents the equipment from being damaged by unstable current and voltage shock during charging; it can charge and discharge the product to provide charging protection, discharge protection, temperature protection and leakage protection. Multiple protections such as overload protection and short circuit protection make the product performance more secure and stable, so that the product itself has a longer service life, and at the same time avoids the unstable output to cause damage to the mobile phone. 3. Boost chip: The voltage of the mobile power battery is 3.7V, and the output voltage is 5.0V. The power needs to be output through the booster circuit. Now there are manufacturers to provide a three-in-one solution, all of which are solved by one chip. These chips determine the security, stability and conversion efficiency of the mobile power supply. This article comes from [System Home] www.xp85.com