DESCRIPTION:
The circuitry used to recharge the batteries in portable products, including mobile phones, is crucial in determining the battery life and everyday usability of the product.
The size and kind of the battery being charged determines the charging process (how much voltage or current to use, for how long, and what to do after charging is finished).
Depending on the stage of charging the battery has reached, contemporary battery chargers dynamically adjust the charging conditions. Without any safety concern, a dead battery may be charged more quickly. This is why most benchmarks for charging speed (ours included) quote the battery charging level reached after a 30-minute charging session on an empty battery.
Any charging speed greater than basic chargers’ 5V/1A output, which equates to 5W of electricity, is referred to as rapid or fast charging.
QUICK CHARGING
The quick charging market is still incredibly fragmented, and nearly every manufacturer has its own solution—often using proprietary technology.
The most popular option is 5V/2A charging, which provides 10W of power and is supported by virtually all other phones. From there and upward, the charging gets really rapid.
The QuickCharge protocol from Qualcomm is compatible with smartphones using Qualcomm chipsets. It has through several iterations, the most recent being QuickCharge 4+. The most widespread implementations have a peak power output of 18W and are backwards compatible with earlier versions. Even though Motorola markets their phones as having TurboPower and makes no mention of QuickCharge, they nonetheless adhere to this standard.
Similar to Qualcomm, MediaTek has also released its own proprietary chargers and charging protocol dubbed Pump Express. This protocol is supported by phones running MediaTek chipsets. PumpExpress 3.0, the most recent version of the standard, has a USB-C connection for the charging cord. There is also the more affordable Pump Express+ 2.0 option, which supports the usage of a microUSB connection.
Another rapid charging method that is not specific to one piece of hardware is USB Power Delivery. It does need a USB-C to USB-C connection, but it doesn’t need any proprietary hardware. There are also laptops that employ this standard for charging, thus the maximum power output is 100W. Nevertheless, current smartphone implementations can only generate 18W of electricity.
Because Oppo, Vivo, and OnePlus share certain intellectual property and R&D, their phones employ comparable rapid charging technologies. Oppo refers to it as VOOC Flash charge, Vivo refers to it simply as Rapid battery charging, while OnePlus formerly referred to it as Dash charge (now renamed to just OnePlus Fast Charge for legal reasons). The three models all provide 18–20W of electricity.
The three manufacturers, however, who are leading the rapid charge revolution, came up with even quicker implementations in 2018, and they did so by introducing new names, which made things a little bit more perplexing for the less experienced customers. The Super VOOC Flash Charger from Oppo has a 50W power output. The Dual-Engine Quick Charging system from Vivo has a 22.5W power output. Last but not least, OnePlus’ Warp charge can output up to 30W.
In addition, Huawei’s premium smartphones come with a patented rapid battery charging technology dubbed SuperCharge, which has a 40W power output capacity but is most frequently limited to 22.5W.
The mCharge system from Meizu, which is also proprietary, is already included in a couple of their more expensive models. It has a maximum power output of 24W. Meizu has also demonstrated their upcoming Super mCharge technology, which can give up to 55W of power, although as of the time of writing this, it has not yet been integrated into a smartphone.
WIRELESS CHARGING
An electromagnetic field is used to transmit energy between two items by electromagnetic induction in wireless (or inductive) charging. To use induction, just place a gadget with an induction coil directly on a special charging station (or charging pad).
Unlike in the past, when there were at least a few rival wireless charging protocols, today the entire mobile market uses Qi (pronounced “chee”).
Wireless charging may be done at various speeds, just like with conventional cable charging. A Qi charging pad’s maximum power output is 5W, while faster chargers can currently deliver up to 15W to compatible phones.
The Qi standard mandates that all hardware be backward compatible, therefore regardless of the maximum power output permitted by the charging pad and the smartphone, every Qi pad is compatible with all Qi-enabled devices.