With the development of smartphones today, fast charging has almost become a standard configuration. In the Android camp, fast charging development is quite popular. While Apple is thinking of introducing 25W fast charging on the iPhone 13 series, the Android camp is already working on 200W fast charging. The likes of Huawei, Oppo, Xiaomi, Vivo, etc. are all working hard on fast charging function – from 20W a few years ago to 120W presently. It is important to note that fast charging technology is a “system engineering”. This means that requires the combination of different aspects to form a system. We have the fast charging devices, chargers, and charging protocol as individual aspects of fast charging technology. With the progress of the fast charging development, it appears that there will be a bottleneck moving forward. Here are the top five (5) trends in the smartphone fast charging industry as of now
1. High power charging (charging speed) is not all there is
Before now, there was this impression that once a smartphone supports high-power charging, that’s all. High power is no longer the only force point for fast charging. In just 7 years, the charging rate has jumped from 20W to 200W all the way, and it’s now a standard for most smartphones. With the industry working on 200W, we are now at the “peak” of high power charging. This is not to say that there will be no more increase, but the increase will be slow. At this point, fast charging is no longer just a race of speed, and the anchor point of industry competition is gradually shifting. Now, there will be a tussle to improve the user charging experience.
Since we have been focusing on speed, there has been not much focus on battery safety hazards, battery aging, and chaotic charging protocols. Now, the new competition will be in these areas. The industry is now moving away from charging speed to some other areas as we will see below. From slow charging to fast charging, charging speed has always been an important subject of competition. As the industry enters the “post-fast charging era”, seeking speed is not the only focus.
2. Charging safety is becoming more critical
According to an industry expert, “No matter how the charging technology develops, safety is always the primary factor,”. In the fast charge era, faster-charging speeds require high-rate charging and discharging of batteries, which speeds up the reaction speed of chemical substances inside the battery. Only the reaction speed of polymer batteries can accept larger currents. Otherwise, high-rate, high-capacity, high-speed will bring more security risks to the mobile phone charging system.
According to Anker’s consumer research, the pain points of consumers’ demand for chargers are no longer faster charging. Users are now looking for “safer charging experiences”. The improvement of charging safety mainly includes three aspects
- To improve the conversion efficiency through new materials
- Monitoring the battery safety through the built-in power management chip
- Use of new technologies and structure design, etc. to inject safety guarantees.
New materials are silicon-oxygen anode batteries and graphene batteries
A senior engineer from a veteran mobile phone manufacturer said that in the exploration of new battery materials, silicon-oxygen anode batteries and graphene batteries are the directions for the industry to seek breakthroughs.
Most manufacturers (whether smartphone manufacturers or third-party) now use a built-in power chip to ensure battery safety.
For example, a battery safety detection chip can monitor the voltage drop in real-time and intelligently detect whether the battery has internal damage. Oppo and Xiaomi have a technology like this. Third-party manufacturer, Anker, uses power management chips in its charger.
New technologies and structure design
A couple of manufacturers are already working on new technologies to ensure safer fast charging. We have developments in low-impedance fuses, gallium nitride (GaN) electronic switches, internal series double cells, sandwich safety batteries, and more. The sandwich safety battery protects the internal short circuit of the battery from any external force that could cause damage. The “sandwich safety battery” refers to the use of composite current collector technology (a new type of composite material as the matrix), and two layers of aluminum are plated by cutting-edge technology to form a “sandwich” structure with coating on both sides of the structure. All these will also be within a cover safety protection layer to form a five-layer safety protection structure.
Tests from a couple of manufacturers show that this structure passes the acupuncture and heavy object impact test 100%. There is absolutely no effect on the battery after impact. We can now see that there is active development in battery protection.
3. Battery technology is evolving
Fast charging is essentially a complex system engineering. This system includes charging adapters, cables, PMIC integrated power management circuits, batteries, and many other aspects. It is far from enough to increase the power of the power adapter.
Previously, due to the limitations of technological development, various manufacturers have focused on power adapters to increase the charging rate. However, as the fast charging rate increases to 65W, or even more than 100W, there is a need for development. If there is no development, you will have cases of a 100W compatible device charging at 15W.
Battery technology has become a key point in the current fast charging rate.
A senior industry expert said that the next major change in fast charging technology is likely to be battery technology. “Of course, battery technology is the most difficult to breakthrough. Once there is a breakthrough, we will see qualitative changes in the charging industry,” said industry experts.
At present, various mobile phone manufacturers have different strengths in batteries. Xiaomi is more inclined to start from the dimension of new materials. In March this year, it released silicon-oxygen anode batteries. However, Oppo chose to inject AI into battery management to achieve Smart Charging.
Smart Charging technology brings changes to the battery life, charging speed, and temperature
Battery life: After 1500 cycles of full charge and discharge, the battery has 80% capacity. Furthermore, the battery life is 3 times longer than the regular Chinese standard requirements
Charging speed: Intelligently increases the charging speed in specific demand scenarios. In high-demand mode, the charging speed of the 65W super flash charge can increase by another 20%. This will allow the device to get a full charge for a 4500 mAh battery in 30 minutes
Temperature rise performance: According to different usage scenarios, it can intelligently predict the current and heating conditions. It will also dynamically match the charging power, and achieve a balance between the charging speed and the temperature rise.
4. “Normalization” of fast charge protocol
As mentioned earlier, smartphone fast charging technology is a system engineering. In addition to hardware products such as devices and chargers, the charging protocol is also a part of it. This specifies the communication method between the device and the charger.
In the mobile phone charging field, there are currently five mainstream fast charging technology manufacturers with charging protocols. We have Qualcomm, MediaTek, USB-IF Association, Huawei, and Oppo. While the first three are public agreements; the latter two are private agreements.
The smartphone fast-charging industry has always had the problem of protocol incompatibility. This results in only basic low-power charging between branded mobile phones and chargers. In addition to affecting the user experience of fast charging, the incompatibility of the charging protocol also causes a waste of resources to a certain extent, increasing the risk and cost of R&D in the upstream and downstream of the industry chain.
Acceptance of global charging protocols insight
In May of this year, the Telecommunications Terminal Industry Association released the integrated fast-charging standard “Mobile Terminal Converged Fast Charging Technical Specifications”, hoping to promote the interoperability of various manufacturers in the fast charging technology agreement. At present, this standard has been supported by terminal manufacturers and supply chain companies such as Huawei, Oppo, Vivo, Xiaomi, Honor, Silica, Rockchip, Lihui Technology, Angbao Electronics, and Dianku Networks.
In addition, with the advent of USB-C and the expansion of the USB-PD fast charging protocol, the industry has begun to gradually move towards compatibility. At present, more manufacturers have announced compatibility with the PD protocol, including Apple, Samsung, Lenovo, Anker, and so on.
It is not difficult to see that the charging agreement that was previously divided into separate packages is slowly closing. The general trend in the future must be towards unity. Regardless of Chinese or global, the charging protocol will be unified. This is a general and inevitable trend.
5. Wired charging may be replaced by wireless
In addition to the above changes, many industry experts believe that wireless charging is getting so much attention. If this attention continues, it may replace the wired charging.
In recent years, while constantly refreshing the charging rate of wired flash charging, various manufacturers have also made efforts in wireless flash charging. We understand that since 2018, mobile phone manufacturers including Huawei, Xiaomi, Meizu, Oppo, and OnePlus have successively launched wireless flash charging solutions.
The peak is currently Xiaomi’s 80W wireless flash charging. We also have Oppo’s 65W AIRVOOC and Meizu 40W vertical wireless charging. Despite the prospects of wireless charging, there are still some bottlenecks to breakthrough.
Wireless charging bottlenecks
According to industry sources, most of the mainstream wireless fast charging on the market can only charge point-to-point short distances. This is low in flexibility and is not a true form of wireless charging. A senior engineer said, “Future wireless flash charging should be non-contact, that is, when the mobile phone enters a certain range, it can automatically connect and charge,”.
In addition, in terms of conversion efficiency, wireless charging has low conversion efficiency. It also experiences a large power loss and serious heat generation. This calls for a higher requirement for wireless charging speed and device heat dissipation.
According to estimates by the OneZero and iFixit teams, the average wireless charging uses 47% more power than wired charging. It takes an average of 14.26 Wh to fully charge a mobile phone using a wired method. For wireless chargers, it takes an average of 21.01 Wh.
Anker innovative consumer power product research and development Director Li Mingkang said
“When the charging speed is close to that of wired charging, and the cost is approaching the range of wired charging, wired charging may be replaced by wireless charging, but these technologies will take some time to overcome.”
The fast charging of smartphones is actually in a mature stage. However, this does not mean the “stagnation” of the charging rate increase. On the contrary, it is more like a transition from a “rapid advancement to a jogging stage”. This means that the increase in the charging rate is still continuing but many other criteria are now on the agenda. Mobile phone manufacturers will now look away from speed. They will focus on safety, battery life, and other technologies. These will also improve the charging experience of users.