We all care about the longest operational time of our smartphones on a single charge. However, we want to have a more efficient device, which requires more power. Unfortunately, manufacturers are not able to produce a battery that would have a large capacity and was thin at the same time. This is why fast charging techniques are being developed. The leader here is Qualcomm, who has developed a new version of its solution, i.e. Quick Charge 4+.
The first version of Quick Charge appeared 4 years ago. Then, Qualcomm used a fairly simple trick and increased the charging current to 2 A. In the next version, new charging voltage levels were added, namely, in addition to the standard 5V, the Quick Charge 2.0 also supports 9V and 12V. Therefore, up to 18 W power without having to increase the charging current. Currently, most Qualcomm processors support Quick Charge 3.0. The increased voltage range (from 3.2 V to 20 V) allowed the smartphone to continue charging without warming up.
We have not yet met the Quick Charge 4 devices on the market.
Information about the new Qualcomm high-speed charging technology came out in November last year. However, the smart phones we have presented so far do not support Quick Charge 4. This solution is supposed to offer 5 hours of smartphone usage for 5 minutes of charging time. Does it sound promising? Well, this result was obtained by Qualcomm during their laboratory tests with a smartphone with 2 750 mAh battery. Quick Charge 4+ is meant to be even better. Compared to Quick Charge 3.0, the newly introduced technology will be 38% faster. On the other hand, the battery temperature during charging can be as much as 8°C lower. These differences compared to standard Quick Charge 4 are respectively 15% and 3°C better. These gains result from the application of a second charging control circuit that controls the separate charging cables. This means that the current can be routed through cooler areas of the phone. Qualcomm has also worked on security measures that will protect our smartphone even from the effects of a shorted port.
The first smartphone with Quick Charge 4+ will be the ZTE nubia Z17.
The new fast charging technique will be supported by the Qualcomm Snapdragon 835 chipset. However, not every smartphone with this chip will support it. Examples here are all US versions of the latest flagship Samsung Galaxy S7 and S8, which still use the Quick Charge 2.0. Here the limitations are the Exynos chips used in European models. Samsung can not fully exploit the potential of Qualcomm chipsets because they do not want to launch smartphones with different charging speeds in different markets. Also, Xiaomi Mi 6 supports older fast charging technique.