Mobile phone flash charging technology: it can be used for one day after charging for half an hour.
201April 1 1 09:49 Source: Science and Technology Daily
With the development of mobile phone hardware and mobile network technology, the power consumption problem of smart phones has become increasingly prominent, which is characterized by short battery life. "One charge a day, a necessary charging treasure for business trips" is almost the voice of every smartphone user.
According to reports, recently, Israel StoreDot demonstrated the technology of fully charging the battery of the mobile phone in 30 seconds on a Galaxy S4 mobile phone. The 30-second charging technology lets everyone see the "spring" of smartphone life, but it is expected that this technology will not be put into the market until the end of 20 16. Actually, you don't have to wait until 20 16. Compared with other fast charging technologies that are still in the experimental stage, a domestic mobile phone manufacturer has developed a mobile phone flash charging technology and applied it to the OPPO Find7 mobile phone that came out in March. According to the official news of OPPO, for Find 7, you can make a phone call for 2 hours after charging for 5 minutes; Charging 15 minutes, continuous call for 6 hours; After charging for 30 minutes, the power can directly soar to about 75%, which is enough for most people to use all day.
Mobile phone flash charging: first accelerate, then "trickle"
The biggest "pain point" for consumers facing smart phones lies in the battery problem of mobile phones, that is, the battery life of mobile phones. Consumers and mobile phone manufacturers pursue high-quality screen resolution, diverse functions and powerful CPU, which accelerates the energy consumption of mobile phones. At present, many manufacturers choose to increase the battery capacity to solve the battery life problem, but there are great problems in this way. When the battery capacity increases, the charging time of the mobile phone will be prolonged, which will increase the inconvenience of users. Modern people have a lot of fragmented time in life and work, such as meeting breaks, commuting, lunch breaks and so on. The original intention of OPPO to develop VOOC flash charging technology is to make the mobile phone charge quickly in a short time, adapt to and make full use of the fragmentation time, and solve the problem of mobile phone battery life while improving people's time utilization. Technical developers put forward solutions according to users' needs and keep trying. After three years and tens of thousands of experiments and tests, they were finally put on the market. At present, user feedback is very good, and many users say that they are no longer bound by the power of mobile phones.
The reporter interviewed Li Jie, product manager of OPPO Find7. He compared the principle of VOOC flash charging technology of OPPO to driving. Mobile phone charging from 0 to 100% is similar to the whole driving process. If you want to arrive safely, you must step on the brakes at the last short distance, that is, trickle charging, but there is still a lot of room for improvement in the first 90% of the journey speed. VOOC flash charging technology is to maximize the first 90% of electricity.
Break away from convention: fully customize high current process chain
According to the formula of power = voltage × current × time, the charging time can only be shortened by increasing voltage or current when the power is constant. If the method of increasing voltage is adopted, multiple buck circuits need to be designed in the charging circuit, but there are three problems in this method: first, buck requires energy conversion, which will cause a lot of heat in the mobile phone, causing problems such as hot hands and slow running speed of the mobile phone, which will make the user experience worse; The second is safety. The maximum voltage that the battery cell can withstand is about 4V. The greater the voltage, the greater the potential safety hazard, and the safety of 100% cannot be guaranteed. In addition, the charging efficiency is not high enough, which affects the user experience.
The other is to adopt the idea of increasing the current and use the high-current mobile phone charging method to solve the problem of charging and heating, so as to make VOOC "the coolest flash charging in the world". However, there is no precedent for this high-current mobile phone charging method in the mobile phone market. The existing batteries, circuit boards and adapters in the market are not suitable for high current. "When OPPO first put forward the idea of high-current mobile phone flash charging, some suppliers thought OPPO was crazy," Li Jie told reporters. Because OPPO is convinced that this is a technology that is very beneficial to users, it has made a bold attempt. It took nearly three years and a lot of money to set up a research team for flash charging technology. Finally, VOOC flash charging technology came into the market, in which every link such as battery, circuit board, USB interface and adapter was exclusively developed and customized by OPPO. Li Jie said that the investment in R&D of only the 7PinUSB charging interface reached about 100000 RMB, and the cost of the adapter far exceeded expectations, equivalent to 5- 10 times the cost of the existing adapter in the market. "The user value obtained by such a large investment is also very large, and it is worthwhile for users to have a better experience."
Beyond Tradition: "Fast and Safe" Intelligent Control
When charging with VOOC flash charging technology, the current is 4.5A when charging to the front 90% or so. The battery is a custom-made fast charging core, and its cost is much higher than that of ordinary batteries. USB also uses 7pin interface, which is different from 5pin of ordinary charger. It is specially used to carry the large current of VOOC flash charging and belongs to one of OPPO patents. The remaining 10% power is charged by trickle, that is, it is returned to the ordinary adapter to ensure the "smooth landing" of charging. Because the first 90% of electricity is charged with high current, it can reach 75% in 30 minutes and 100% in about 70 minutes. However, in the environment of 5V×2A, it takes at least 1 hour for ordinary 3000mA battery to be fully charged with 75% electricity, and it takes 2 hours to be fully charged. After comparison, it can be said that OPPO technology has indeed improved the charging speed of mobile phones. After getting up in the morning, users can use the washing and breakfast time to charge, and 75% of the electricity can basically be used for one day in 30 minutes.
In addition, for the security of mobile phone charging, OPPO adopts 5-layer protection technology, while ordinary charging technology has only 2-3 layers of protection and no physical protection. The flash charging of OPPO Find7 not only makes a fuss about the charger, but also realizes five-layer protection from the charger to the interface and then to the mobile phone. Among them, the adapter has two valves, and the MCU intelligent chip monitors the voltage and current, which is similar to the gearbox of an automobile and plays an adjusting role. Mobile phones also have two layers of protection. The first layer "shakes hands" with the adapter to judge whether the mobile phone supports flash charging, and the second layer adjusts according to the current. The last layer is the most unique and killer, which is battery fuse protection. When there is an abnormality, the fuse in the battery will be blown immediately, and the circuit will be physically cut off to ensure the absolute safety of charging.
Future outlook: continue to upgrade+launch new products.
OPPO is expected to launch VOOC flash charging version 2.0 in the future. Li Jie said that because it is completely based on the most conservative and safest way, the later upgraded version will continue to improve the charging speed.
In addition, Li Jie revealed that OPPO will launch two new fast-charging products at the end of July. One is a mobile power supply with flash charging, which will reach the speed of flash charging whether charging the mobile power supply or charging the mobile phone with the mobile power supply; The second is fast car charging, which is as fast as VOOC flash charging, providing more convenience for charging mobile phones that conform to modern lifestyles. In the 4G era when mobile phones are used more frequently, VOOC flash charging provides a new solution to the power consumption problem of smart phones.
Excerpted from China News Network-Financial Center -IT Channel, here are pictures.