Wireless charging technology has been around for more than 100 years, but its inclusion in flagship devices has given it a new life. Since the late 19th century when electricity pioneer Nikola Tesla demonstrated magnetic resonant coupling the ability to transmit electricity through the air by creating a magnetic field between two circuits, a transmitter, and a receiver.  

However, wireless charging provides a very easy method of charging as it does not require the phone or other device to be physically connected to the charger. As technology has evolved, so too has the speed at which a phone can wirelessly charge.     

How does it work?   

Wireless charging uses a base station or charging pad to transmit power using electromagnetic waves. This electricity is then used to charge the smartphone. The power transfers to the device via induction, which will work through some smartphone cases if they're thin enough and the material doesn't create interference. 

The most popular wireless technologies now in use rely on an electromagnetic field between two copper coils, Qi wireless charging technology as it currently stands can transfer up to 15 watts of power via wireless induction.

How fast wireless charging is?

The kind of phone you have and its power compatibility can make a profound difference in how fast and efficiently a wireless charger can power up your phone. You will need to check the speed at which your phone can wirelessly charge, which is usually given in terms of 7.5 watts (W), 9W, or even 15W. Sometimes software plays a part in the speed. Right now, 10 watts is all you'll need if you want to get the fastest possible wireless charge out of your device, which typically translates to full recharge times in the roughly three-hour range, but that can vary.

Do keep in mind that as fast as wireless chargers have become, the included charger for most phones will be your best bet when you're in a hurry and need as fast a charge as possible.  

What are the downsides?

The main drawback of wireless chargers has been slow adoption and slow charging, and currently with wireless charging your smartphone has to stay on top of the charging pad to continuously charge. Whereas with a cord you are at least free to move around the diameter of the cord. It's more costly to purchase a wireless charging pad, especially when new smartphones come with a corded charger in the box. 

So portable wireless packs aren't great at providing the quick bursts of charge you often need when you're on the move.

What are the factors to consider before buying a wireless charging station?

Buying the right wireless charger can be surprisingly difficult. Make sure to consider these factors before buying any wireless charger:  

Power

Look for the wattage speed on the box or in the specification listing for a charger, then compare that with the speed at which your phone can charge.

Qi charging

Qi charging is the universal standard, so if you have multiple different wireless-capable devices, you can use the same charging pad without any issue. This may seem obvious, but there are a couple of other wireless charging standards out there, so make sure whatever you pick up supports the Qi standard. The efficiency of Qi charging is still lower than cable charging, so it takes more time to charge wirelessly using the same amount of power.  

Brand   

As the phone you are charging is a costly item of electronics, it may not be worth saving on the last bit of money to buy a cheap wireless charger.  

If you're in doubt, stick to brands with a good reputation for charging gear.