Recently, the iPhone 8 / 8P / X release, and finally joined the much-anticipated fast-charge function, compared to early in the morning to achieve fast-charge domestic mobile phone, is late for many years. So, two days ago, gave my girlfriend sent a new mobile phone charger, the result was furious sprayed meal: "fast charge very hurt the battery! Do you want to give me a new phone?" Obviously this sentence is Do not understand the fast charge technology. In order to let everyone understand this thorough things, WST do work, give you a lesson, understand the battery aging is exactly what causes, to solve this misunderstanding.
The principle of fast charge is actually very simple
Now the battery capacity of the phone is generally more than two thousand or two thousand mAh, the use of traditional 5V / 1A charger, filled with a battery at least three hours or more time, more than an hour before the Nokia mobile phone is full of electricity, a lot of time. With the battery capacity, the original charger power can not meet the needs of charging, so fast charging technology appeared.
The major mobile phone manufacturers have launched their own fast charging technology, the principle is to improve the charging current and voltage, to really high-power charging. In simple terms, the input power of the charge port = input voltage x input current. General mobile phone charger will have a charging curve, by controlling the different voltage and current, to achieve the highest charging efficiency. In general, the most efficient way to start the constant current charge (charge faster), and then the constant voltage charging (charging speed down, because the battery itself voltage up), and finally trickle charge (in full After compensation for self-discharge caused by the loss of capacity).
Most mobile phones are now using Qualcomm Quick Charge charging technology to achieve, from the beginning of the 1.0 standard, to the latest 4.0 standard, the higher the standard higher charging efficiency. QC 1.0 breakthrough USB-IF USB Battery Charge 1.2 on the agreement, the voltage and current increased to 5V2A, charging time by 40%. Fast upgrade really from the QC 2.0 start, through the handshake agreement, so that the charger and the phone to identify each other, handshake and then increase the transmission voltage, up to 20V, although the current unchanged, but the efficiency of charging increased by nearly 75 %.
QC 3.0 is based on the 2.0, the introduction of the best voltage intelligent protocol (INOV) algorithm, accurate control of the charging voltage, the input voltage reaches 200mV a file adaptive adjustment, performance has improved nearly 38% while reducing Loss, at this time by virtue of the voltage controllable, current upgrade to 3A. At present, the mainstream fast-charge mobile phone application is QC2.0 and QC3.0 standard. To QC 4.0 is a more sophisticated intelligent adjustment control voltage, the accuracy of 20mV to a file, the charging current and voltage becomes more flexible, with a constant 3A or non-constant 4.7A-5.6A, the voltage does not need to reach 20V So high, in the 5V-9V between the intelligent control, and ultimately have nearly 20% of the speed increase, efficiency increased by nearly 30%.
Fast charge technology, the reason for the need for more sophisticated current and voltage control, the main reason is to be able to get more extreme charging curve, in the front of the charge, high-power charging allows users to get the shortest possible time the maximum power, the remaining uncharged Battery capacity, it is gradually slow down the way to complete the charge, to protect the battery and circuit.
The mechanism of battery aging
Cell phone batteries used in most of the lithium-ion battery, we said that the battery aging refers to the daily use of lithium-ion batteries in the aging of aging. Why is there an aging phenomenon? Give you about the popular science of lithium batteries: lithium ions can be in the anode and cathode of the electrolyte through the line, resulting in the equipment for the energy supply. The so-called battery capacity, can be easily understood as the battery (in charge and discharge) back and forth the number of lithium ions running.
Materials that make up the battery electrode often break down, allowing some metal ions (especially manganese ions) to float freely and run to the opposite electrode, and then trapped lithium ions. When the manganese ion (above gray) is stripped from the cathode (blue area) of the battery, it reacts with the electrolyte near the anode (gold) of the battery and captures lithium ions (greenish above). With the passage of time, more and more lithium ions can not be put into normal work (locked), the battery capacity and therefore gradually reduced, resulting in decreased battery life.
Why is it aging?
1, overcharge and over discharge
There are many reasons for the aging of the battery, first of all natural aging. Even if the normal use of lithium ions will be self away from the anode, gradually aging, but the aging rate is slower; and in daily use, charging over, the battery over will increase the aging of lithium batteries. Now the phone is usually rectified regulator design, when the charge is full, the charger power supply, it will disconnect the charging circuit, the direct use of power lines to power the phone. If you do not use the original charger, it is likely not to cut off the power in time to continue charging the full charge of the battery. Will accelerate the loss of lithium ions, damage the battery, causing the battery aging; and battery power exhausted, free movement of ions will be trapped, the same loss of battery capacity.
2, the temperature is too high / too low
In addition to overcharge and over discharge, the battery temperature is too high, too low, will also affect the battery life. The frequent discharge of the battery will heat, the actual use of the process will cause the battery temperature is too high. So when we play a large game or run other power programs, you need to pay attention to heat and control the program running time. The same temperature is too low, lithium ion activity decreased battery performance and charging performance is also greatly reduced, if forced to charge, the same will affect the battery life. So in a cold environment, mobile phones, notebooks, unmanned aerial vehicles and other equipment, need to preheat the battery to reach a certain temperature before the normal work.
3, the current is too high
In addition, the charge current will also affect the battery life, the battery charge, the current is too high, the battery damage will be particularly serious, and even cause short circuit, explosion, burning, etc., the general manufacturers of original products will have Charge the protection circuit to control the battery charging current is too large, and in some cottage cradle, universal charge, if not joined the protection mechanism, the consequences are very serious.