As more devices adopt wireless charging, how much will technology improve? Here’s how fast wireless charging works and how it will likely get even faster in the future.
How wireless charging works
Most of today’s most popular electronic gadgets – from high-end mobile phones to wireless headphones – come with wireless charging. Apple, Samsung and LG have implemented this feature on a wide range of their devices.
Wireless charging allows users to place their device on a cradle that is plugged into the wall, then it simply begins to charge – no cables required.
Most modern wireless chargers use a process called magnetic induction. This involves transforming the magnetic energy from the charging cradle into electrical energy via a coil inside the device. This energy is then used to charge the battery. This is also why more and more devices are made of glass instead of metal – glass is much more advantageous for induction.
Wireless is one of the most standardized forms of charging. Unlike wired chargers, which require a variety of standards and connectors, most wireless charging devices use the Qi standard established by the Wireless Power Consortium (WPC). This means that a single standard charger will work with both an Apple Airpods case and a Galaxy Note.
Speed up wireless charging delivery
Fast charge works by increasing the number of watts supplied to a phone battery. However, it has to work both ways. Manufacturers also need to design their receiving devices to handle fast charging. Additionally, accessory manufacturers need to increase the potential output of their chargers or transmitters.
In the past, wireless charging was slow, clunky, and offered little flexibility in terms of positioning. Early iterations could only charge 5 watts or less, which was significantly lower than wired charging.
Now, standard wireless chargers using the Qi standard can charge up to 15 watts on compatible devices. This faster charging rate is called the Extended Power Profile (EPP).
Wireless charging uses a method similar to wired for supplying power. This involves powering a device at full speed and then turning it down towards the end of the charge cycle.
It follows this process:
Detection: The transmitter detects if a Qi-compatible device is on it.
Full power: If the receiver is on the latest version of Qi, it will get up to 15 watts of power from the compatible transmitter.
Heat detection: Transmitters have a thermal test, which allows them to detect if a device is getting hot. If so, the transmitter will slow down its output power.
Completion: When the receiver’s battery is full, the Qi pad will stop charging the device.
This process ensures the safety of your devices and prevents them from overheating the batteries are not damaged. It also ensures that a device will not be overcharged from the transmitter, so that you can safely leave your phone in a charging cradle overnight.
Custom wireless standards
the basic Qi standard was last updated in 2015 which brought PPE and improved heat sensitivity. Since then, the EPP Power Class 0 has been released, which allows transmitters to deliver power of up to 30 watts, depending on the receiving device.
Although this charging speed has not been standardized in all areas, many manufacturers have implemented modified versions of the Qi EPP standard capable of delivering higher speeds. One of those companies is OnePlus, which launched a 30-watt wireless Warp charger with its flagship 8 Pro. The company claims it can support charging a device to 50% in just 29 minutes.
The charging cradle also has a built-in fan that allows it to achieve higher charging speeds, as well as surge and overcurrent protections. However, it is only compatible with certain OnePlus devices. Other companies, like Xiaomi, have also launched 30-watt Qi wireless chargers.
The future of wireless charging
Wireless charging will only keep getting faster. The WPC has already teased its next step will be a 60 watt wireless charging standard. This speed would be comparable, if not superior, to wired charging speeds of many manufacturers today.
As the transmitters increase in power, they will also be able to charge a wider range of devices. In addition to the increasing speeds for charging mobile phones, this means that electronics with significantly larger batteries, like laptops, will also be Qi compatible in the future.