electric charging made easy

researchers at aalto university in finland have developed a novel method of power transfer that can charge movable devices without the need for messy cables or plugs. wireless charging tiles are laid across a large surface such as a warehouse floor so that devices can be powered up from any point. if scaled up, the technology could be applied to power electric vehicles while they’re on the road.

the research team has tested the design with commercial warehouse robots in cooperation with finnish firm solteq robotics. ‘taking this technology out of the lab and seeing it work in the warehouse was an exciting moment for me personally,’ says prasad jayathurathnage, the postdoctoral researcher who led the project. ‘I was finally bringing the product of ten years of research out of the lab.’

as well as industry and transport applications, the new technology could also be used to improve everyday life. ‘take kitchen appliances, for example,’ continues jayathurathnage. ‘at the moment, you need to put a rice cooker or a blender at a particular spot for it to get energy. but with our technology we can make the whole kitchen counter a source of power for appliances or even phones, but the electromagnetic field is only generated under the devices.’

new wireless power transfer technology could charge electric vehicles on the go
wireless charging of a retail robot at a test site

image: prasad jayathurathnage / aalto university

how does it work?

the transmitters are arranged in a grid with the current in neighboring transmitters running in opposite directions to create a chessboard-like grid of ‘positive’ and ‘negative’ transmitting coils with a magnetic flux between them. a receiver then captures the magnetic flux between positive and negative transmitters, which generates an electric current to charge the device. 

the system functions without any positional tracking or communication between the receivers and transmitters. it also means that power is only transferred to the receiver, rather than the entire area, making it possible for several devices to be charged at the same time. when tested, the researchers found that the devices charged smoothly even while moving around.

new wireless power transfer technology could charge electric vehicles on the go
example of a mobile warehouse device on the charging tiles

‘the beauty of our method is that it’s very simple yet quite sophisticated,’ says jayathurathnage. ‘we don’t need a high-end processor or lots of computations to make the transmitters intelligent. at the end of the day, it’s all an electromagnetic system, and our approach was to figure out how we could detect the receiver’s presence and position electromagnetically.’

the next challenge is to increase power levels from about 1 kW to around 20 kW so that the technology could be used to charge EVs. ‘there are pilot projects on electrifying roads across the world,’ says jayathurathnage. ‘electric vehicles are a really great application of this technology.’

the research has been published in a paper here.

new wireless power transfer technology could charge electric vehicles on the go
the technology could be scaled up for electric vehicles