We know graphene has the potential to improve battery performance, and it is this immediately applicable and potentially lucrative line of research that has caught the attention of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The team there has created a new layered composite of graphene and tin which could provide high capacity batteries with short recharge times, perfect for things like electric vehicles.
From the Lab’s press release: “For an electric vehicle, you need a lightweight battery that can be charged quickly and holds its charge capacity after repeated cycling,” says Yuegang Zhang, a staff scientist with Berkeley Lab’s Molecular Foundry, in the Inorganic Nanostructures Facility, who led this research. “Here, we’ve shown the rational design of a nanoscale architecture, which doesn’t need an additive or binder to operate, to improve battery performance.”
The structure of the composite is very cool. Initially, the researchers created alternating layers of graphene and tin to build up what they have called a sandwich structure. This is heated to 300˚ Celsius in a hydrogen and argon atmosphere. During this process, the tin layer forms into pillars, increasing the gap between each graphene sheet. This larger gap improves the “electrochemical cycling” of the battery. That is, you can charge it quickly, and again and again, without degrading the performance.
The work has been published in Energy and Environmental Science.