Wireless charging will soon be available for more and more mobile phones. VTT
Technical Research Centre of Finland is working with the industry’s leading
technological companies and standardisation bodies to expand the scope of
application of wireless charging technology to other, smaller portable
devices, such as mobile phone accessories, wrist devices, wireless mice and
sensors. This can be done by combining wireless power transmission with NFC
connectivity technology, which enables cost-effective and compact design.
Consumer need to recharge the batteries of various kinds of portable devices,
whenever and wherever, continues to grow. Over the next five years, wireless
charging will be available for more and more mobile devices. The first mobile
phones with wireless charging capability are already on the market. Examples
include recent smartphone releases by leading mobile phone manufacturers, many
of which have wireless charging either built in or available through a special
cover accessory charging case.
The increase of features in mobile devices has caused cost pressures,
increased power consumption, and created new challenges for keeping devices
sufficiently compact. Combining wireless charging with NFC (Near Field
Communication) technology makes it possible to design increasingly compact and
cost-effective wireless charging circuits, which is essential especially for
small devices. In the near future, NFC devices will be able to receive
electrical power wirelessly, as well as acting as charging platforms capable
of transmitting wireless electrical power.
The challenges include, among others, current NFC antenna circuits which have
not been optimised for efficient, wireless energy transfer. In addition to
technological development, introducing NFC-based charging to commercial
products requires amendments to the NFC standards so that they also support
the design of open interfaces, both in the device to be charged and the
wireless charger devices. This work is under way at the NFC Forum.
In future, small devices can be placed on a laptop PC that operates as a
NFC-compatible charging plate. In this way, using separate charging
accessories and plugging in charging cables can be avoided. At the same time,
the devices can utilise their NFC connectivity e.g. for downloading
measurement data from the device to the PC and for reprogramming the device to
VTT develops technology for wireless charging over NFC and is an active
contributor in its standardisation at the NFC Forum Wireless Charging Task
Force. The picture shows an NFC compatible charging plate developed by VTT.