What Is Wireless Charging & How Exactly Does It Work? [MakeUseOf Explains]
We live in a wireless world. Except we don’t. Sure, we can send huge amounts of information across the airwaves, but the devices capable of sending and receiving it are tied down to power cords. Batteries allow some freedom but, eventually, we all have to come back around to the familiar face of the power outlet. What if we didn’t? What if we could charge anywhere, at any time?
Wireless chargers seem like magic at first; you put your phone on a special platform, leave it for a bit, and you return to a fully-charged phone. However, wireless charging isn’t as mystical as you may first think, and you can easily understand it once you break it down.
Let’s explore how wireless charging works and what it means for the future of technology.
How Does Wireless Charging Work?
So, what is wireless charging? This technology takes advantage of a technique called “inductive charging.” This has been around since the late 19th century but didn’t really take off until recent times.
Using Coils and Oersted’s Law to Transfer Energy
Inductive charging works by utilizing something called “Oersted’s law.” This states that when an electric current flows through a wire, it generates a magnetic field.
Even better, if you create a tight coil and run electricity through it, it creates an even stronger magnetic field. This little coil is what you’ll find in a wireless charging pad—it’s sitting there, converting an electrical current into an electromagnetic field, waiting for something to come along and “take” that energy.
Of course, you can’t just hold a battery in a magnetic field and expect it to charge up. You have to set up a receiver that can take this electromagnetic field and convert it back into an electric current. In this example, the best receiver happens to be yet another coil.
To transfer electricity through the air, you can put an electric current through the induction coil and then place a receiver coil nearby. The induction coil turns the electric current into an electromagnetic field due to Oersted’s law.
If a receiver coil is placed within the field, it takes the electromagnetic energy and turns it back into electricity. You can then direct this electric current wherever it needs to go—like into your phone’s battery, for instance.
Why Isn’t Wireless Charging Technology Used Everywhere?
It sounds like a scientific marvel of the 21st century, but again, we’ve known about this technology for over 100 years. While it was interesting that electrical energy can travel through the air, the technology is a little limited.
For one, the induction and receiver coils need to be mere millimeters apart from each other. This is because the magnetic field the induction coil generates isn’t that big, so you need to coddle the two coils together to get a flow going.
This is a major disadvantage versus a technology such as Wi-Charge. This technology has a wireless charging distance of 30 feet without needing to be “paired up” to each charging device beforehand.
Second, the charging rate is slow-going compared to wires. Wireless charging needs to charge up a coil and transfer that energy to another coil over a millimeter gap, at which point you might as well cover that gap using a wire!
As such, for a long time, wireless charging only saw use in healthcare and electric toothbrushes. It wasn’t until recently when we began seeing the same technology added to smartphones.
Nowadays, if your phone supports wireless charging, you can purchase a little platform to place your phone on. This platform contains the coils that transfer energy to your phone.
What Is Qi Wireless Charging?
To make things even more confusing, there are different standards for wireless charging. This is like how different phones use different charging ports to fill their battery; one type of cable won’t fit every phone in the world.
Despite this, however, wireless charging has its own main standard, much like how many phones use USB 3.0 cables to charge up these days. The biggest standard in wireless charging right now is called Qi (pronounced “chi”).
You’ll find Qi charging in all the major phone brands, from iPhone to Google Pixel to Samsung Galaxy. You can also find that some third-party wireless chargers will also support the Qi standard, including some wireless chargers that are cheaper than Apple’s.
As for how Qi wireless charging works, it uses the same concept as we covered earlier. By creating a standard around the technology, however, it’s easier for wireless charger manufacturers and phone designers to get their products in sync and ensure the phone is getting the right amount of charge.
The Advantages of Using Wireless Charging
If you’re thinking about using wireless charging, there are some advantages to the technology. For one, it’s great for people who forget to plug in their phones. Just put the charger pad where you usually put your phone, and it’ll charge while not in use.
Wireless charging also means you don’t have to plug and unplug a cable into your phone every time you want to charge it. Over time, a port will show signs of wear and tear after seeing daily use. A wireless charger, however, won’t suffer the same damage.
The Disadvantages of Using Wireless Charging
So why aren’t we all charging our phones wirelessly? As it turns out, there are some problems with the current technological level of wireless charging.
First of all, wireless charging isn’t great for phone addicts. If you’re one who likes to grab your phone every five minutes to see what’s happening, you’ll find a wireless charging pad frustrating. Wires can stay in while you use the phone, but a wireless charger needs to be properly seated whenever you remove and replace the phone.
Second, wired charging is a lot faster. If you’re someone who appreciates a fast-charging phone, you should stick to cables.
As you can see in the video above, DionVideoProductions tested both wired and wireless on the iPhone X. Wired charging charged 51 percent of the batter in an hour. In comparison, wireless managed 38 percent in the same timeframe.
However, this may change in the future. After all, Xiaomi released a wireless charger that could charge a phone’s battery in 20 minutes. As such, we may not need to wait very long before wireless charging speeds rival that of a wired charger.
Removing the Wires From Phone Chargers
Wireless charging isn’t perfect, but the technology is still in its early days. Now you know how it works, as well as the advantages and disadvantages of this technology.
If you want to take advantage of this fancy way to charge your phone, why not grab a new phone that comes with wireless charging? There’s a wireless charging phone for every budget, so you’re bound to find something that fits your needs.
Image Credit: Andrey_Popov / Shutterstock.com
Want wireless charging in your next phone? There are Android phones with wireless charging for every budget. Read on to see our favorites.
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