Scientists have discovered a new way to manipulate graphene to create a material with record energy and power density.
This new form of graphene, when incorporated into energy storage devices called supercapacitors, could be the key to high-capacity, fast-charging energy storage that can deliver power faster than traditional batteries, the researchers said in a statement.
you may like
Pouch cells are used in electric vehicles, drones, wearable electronics, laptops, smartphones, and tablets. Building them from M-rGO could lead to improvements in overall capacity, charging time, and the ability to power more complex and power-hungry devices with smaller batteries, the researchers say.
absorb power
While traditional batteries store energy through chemical bonds, supercapacitors are electrochemical capacitors that store energy as separate charges on the electrode surface. Compared to traditional batteries, they have advantages in terms of energy density (how much energy they can store in a specific space) and power density (how quickly they can deliver energy per unit volume).
But until now, supercapacitors have been hampered by one significant limitation. That means supercapacitors can only use a fraction of the potential energy storage of the material they are made from.
This limitation is due to graphene’s physical structure. This has the advantage of allowing for higher density electrodes (the solid conductors in the battery where charge is stored), but its use of space is highly inefficient. For example, simply stacking graphene on top of each other is inefficient because the sheets get too close together and don’t leave enough space for the ions that need to move in and out to store energy.
To get around this problem, scientists built messy 3D structures that resemble sponges. This provides both a large storage area and a path for the movement of ions. Although lightweight, the downside is that these structures are large and cumbersome.
This breakthrough overcomes that problem by heating graphene in a two-step process. This forms an intertwined, curved graphene network with multiple levels of structure, allowing rapid movement of ions while providing a lot of surface area for energy storage.
“This discovery has the potential to build fast-charging supercapacitors that store enough energy to replace batteries in many applications, and to deliver it much more quickly,” Mainak Majumdar, professor of mechanical and aerospace engineering at Australia’s Monash University, said in a statement.
Source link
