Battery life challenges two major fast charging technologies to solve troubles
with the advent of the era of intelligence, intelligence has become indispensable in people's daily life, but intelligence consumes a lot of power, takes a long time to charge, and the batteries are lithium batteries. Continuous charging and discharging of batteries will reduce the service life of batteries, so the battery life has become a huge challenge, and how to realize the rapid charging of batteries has become the key to solve the problem
for more than 100 years since French scientist Prandtl invented the lead-acid battery, the battery charging has been using the low current (about 0.1C) constant current charging method. Due to the long charging time and low charging efficiency, this method limits the application of the battery. In the mid-1960s, American scientist Thomas put forward the basic law of fast battery charging -- Marx's three laws. After that, people began to pay great attention to the fast battery charging. For decades, people have conducted a large amount of in-depth research on the mode of fast charging and the control method of stopping charging, and put forward a variety of practical methods
(1) continuous high current fast charging mode: it is to quickly charge the battery with continuous high current first. When the battery voltage rises to the point where it is difficult to bear the charging current, it will be transferred to the trickle of 1mm thick graphite sheet, which can peel off 3million layers of graphene; It is hard to charge until the battery is full
(2) charging current decreasing fast charging mode: it is usually called charging current fast charging mode along the acceptable charging current curve, and the charging curve is shown in the figure
1
the curve in the figure is the maximum acceptable charging current curve of Mars, and the broken line is the actual charging current curve. At the beginning, in order to get close to the curve as much as possible, first charge with a constant current that is close to the curve. When the battery can no longer accept such a large current, it will adjust the charging current to a relatively small value, and then charge with this constant current. In this way, repeat the cycle, and keep following the curve of the maximum acceptable charging current until the battery is full. In principle, this charging method is relatively close to the maximum acceptable charging speed of the battery, but in the practical application at home and abroad, there are problems: first, this fast charging mechanism is difficult to design, because the acceptable charging current curves of various batteries and batteries from various manufacturers are different, so it is difficult to be compatible; Second, this chemical material is easy to produce polarization during charging, which is difficult to eliminate in this way, so the charging time is not as fast as ideal
in recent years, fast charging technology has been used and favored by more and more manufacturers. The classic line "charge for five minutes, talk for two hours" is the best slogan for fast charging. Now many Android flagship have fast charging technology, but Apple has not added this function. However, some people worry that fast charging will damage the battery. So what is fast charging? Will fast charging damage the battery
modern fast charging is a relatively general concept, which has three different realization forms: (1) constant voltage, increasing current; (2) Keep the current constant and increase the voltage; (3) Both voltage and current are increased
at present, there are two real fast charging technologies: one is flash charging technology, and the other is Qualcomm's quick charge 2.0 technology. Both of these two technologies require the combination of "charger and", and the lack of one will affect the effect
what is flash technology
the flash can be realized in two ways: one is the segmented charging current control. In short, in fact, when the battery power is low, a larger current is used for charging. As the charging voltage increases, the charging current decreases step by step, which is the so-called segmented charging current control
this is like injecting water into a water polo. At first, the speed of large water injection is fast, but the water polo is likely to explode; It's safe to inject water with a small amount of water, but it's too slow. The solution is to slowly inject water at the beginning, then increase the water flow to accelerate, and then reduce the water flow when it is close to the maximum capacity. This method achieves a balance between time and capacity
another is the multi line setting of charging cable and battery. The charging cable line of flash charging is expanded from ordinary 4-pin or 5-pin to 7-pin. For example, this is like changing the expressway from two lanes to four lanes, and the charged power will also double in the same time
this method effectively solves the problem of battery heating under mainland current, but there will be a compatibility problem of providing one copy of 9.2 random skill file. Because the essence of this flash charging is mainly concentrated on the charger, the charging efficiency will be greatly reduced when using other chargers
at the same time, if you use a flash charger to charge others, because there is no corresponding adaptation, the charging effect is just equivalent to high current charging, and the effect will not be as good as that of flash charging. Therefore, the charger and one cannot be less
the core technology of Qualcomm quick charge 2.0 is to reduce the charging current by increasing the charger voltage, so as to reduce the power consumption on the charging line. There will be a corresponding step-down circuit at the end, which converts high-voltage low current into low-voltage high current
in essence, flash charge and quick charge 2.0 are the same, both by supplying a large charging current to the battery at the initial stage of the battery, and gradually reducing the charging current as the battery voltage increases
the problem of time is an important problem that human beings have been facing. Constantly improving the efficiency of using time promotes human progress and development. From the "big brother" with only call function to the omnipotent intelligent era, its functions have been greatly expanded and developed. Especially after entering the 4G era, the perfect mobile network and open-source intelligent system have enabled applications to achieve a round of explosive development and cover all aspects of life. Entertainment includes listening to music, watching videos, playing games, games, etc; Interaction includes browsing information, spatial information, Weibo, wechat. Currently, HHP4 purchased by Mitsui (Zhongshan) company is 6000 tons/year, and other social chat software; Reading includes learning materials, newspapers, electronic novels, etc. It can be said that applications have been everywhere, involving the corners of life, and have become a necessity for modern people to work and live
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