As power companies grow more belligerent and households start considering leaving the grid altogether; the topic of energy storage is becoming increasingly popular. One development could see solar panels also fulfil the role of batteries by using the same material that creates the electricity – silicon.
Scientists at Vanderbilt University have found a way to create supercapacitors using silicon structures coated in graphene.
While supercapacitors can be recharged much faster and have a longer service life; one of their challenges is size. Energy storage capabilities of supercapacitors is directly tied to the surface area available; meaning the devices tend to be bulky.
The need for a large surface area is being addressed to a degree through the use of nanotechnology to create microscopic ridges, valleys and pores on materials. However, this is still in its infancy and creating and replicating materials is difficult.
Assistant professor of mechanical engineering at Vanderbilt University, Cary Pint, and his team began investigating the potential for using porous silicon; a material with a controllable and well-defined nanostructure that is made by electrochemically etching the surface of a silicon wafer.
After coating the porous silicon surface with carbon (graphene), the researchers found the graphene had stabilised the silicon structure. When used as a supercapacitor, they found vastly improved energy densities compared to those made from uncoated porous silicon and significantly better performance than commercial supercapacitors.
The group is now turning its attention to developing applications such as energy storage solutions utilizing the reverse side of solar cells.
Their work has been described in a paper published in a recent issue of the journal Scientific Reports.
Some of the other novel battery and energy storage technologies we’ve reported on over the years (some of which are now in commercial use):
– Wood battery
– Greener lithium-ion batteries using plants
– Lithium polysulfide
– Sodium-ion
– “Rust” battery
– Zinc air
– Iron phosphate
– Lithium-air
– Virus
– Cavern
– Molten salt
– Beltway
– Flywheel
– Iron based flow
– Vanadium based flow
– Liquid metal
– Silicon air
