What Does Wireless Charging Mean?
Wireless charging, also known as wireless power transfer (WPT), is the process of electrically charging battery-powered devices such as laptops, smartphones and electric vehicles without the need for a wired connection.
Wireless charging can be enabled through three different forms.
- Radio Charging: Uses radio waves to transfer electricity. In this type of charging, the device sits on a transmitter that uses radio waves to charge the device.
- Inductive Charging: Uses electromagnetic waves to transfer energy and charge devices wirelessly. Inductive charging requires the device to come in physical contact with a conductive charging pad that is directly connected to electrical power.
- Resonance Charging: Consists of a sending (sender) copper coil and a receiving (receiver) copper coil at the device end. When the sender and receiver are in close proximity and set to the same electromagnetic frequency, electrical energy can be transferred. Resonance charging may also be referred to as over-the-air charging.
Techopedia Explains Wireless Charging
Although the concept of wireless charging was first proposed by Nicholas Tesla more than a century ago, it wasn't until the widespread adoption of electrical vehicles (EVs) that research moved beyond consumer-grade wireless charging pads for smartphones and tablets.
One of the stumbling blocks to widespread acceptance of electric vehicles has been a lack of a convenient recharging infrastructure. In-depot and on-route wireless charging systems are expected to change that by replenishing power in short bursts whenever the opportunity arises, instead of recharging batteries to full power capacity. This incremental approach to wireless charging is known as "grazing."
Wireless Charging and Electric Vehicles
Wireless charging is seen as a key enabling technology to increase the adoption of electric vehicles. Vendors working to develop standards for wireless power transfer include:
Momentum Dynamics -- known for its inductive charging systems that allow electric buses to wirelessly charge in-depot in minutes.
Powercast -- known for long-range, power-over-distance wireless charging technology that converts broadcasted radio fequency (RF) waves into direct current (DC) power.
Magment -- known for promoting magnetizable concrete slabs that enable wireless charging as electric vehicles drive.