Graphene nanocomposite a bridge to better batteries

Jul 27, 2011
Graphene nanocomposite a bridge to better batteries
Berkeley Lab researchers assembled alternating layers of graphene and tin to create a nanoscale composite. First a thin film of tin is deposited onto graphene. Next, another sheet of graphene is transferred on top of the tin film. This process is repeated and the composite material is then heated to transform a tin film into a series of pillars. The change in height between graphene layers improves the electrode's performance and allows the battery to be charged quickly and repeatedly without degrading. Credit: Lawrence Berkeley National Laboratory

Researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have created a graphene and tin nanoscale composite material for high-capacity energy storage in renewable lithium ion batteries. By encapsulating tin between sheets of graphene, the researchers constructed a new, lightweight "sandwich" structure that should bolster battery performance.

"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 ."

is a single-atom-thick, "chicken-wire" lattice of with stellar electronic and mechanical properties, far beyond silicon and other traditional . Previous work on graphene by Zhang and his colleagues has emphasized electronic device applications.

In this study, the team assembled alternating layers of graphene and tin to create a nanoscale composite. To create the composite material, a thin film of tin is deposited onto graphene. Next, another sheet of graphene is transferred on top of the tin film. This process is repeated to create a , which is then heated to 300˚ Celsius (572˚ Fahrenheit) in a hydrogen and argon environment. During this heat treatment, the tin film transforms into a series of pillars, increasing the height of the tin layer.

"The formation of these tin nanopillars from a thin film is very particular to this system, and we find the distance between the top and bottom graphene layers also changes to accommodate the height change of the tin layer," says Liwen Ji, a post-doctoral researcher at the Foundry. Ji is the lead author and Zhang the corresponding author of a paper reporting the research in the journal Energy and Environmental Science.

The change in height between the graphene layers in these new nanocomposites helps during electrochemical cycling of the battery, as the volume change of tin improves the electrode's performance. In addition, this accommodating behavior means the battery can be charged quickly and repeatedly without degrading — crucial for rechargeable batteries in .

"We have a large battery program here at Berkeley Lab, where we are capable of making highly cyclable cells. Through our interactions in the Carbon Cycle 2.0 program, the Materials Science Division researchers benefit from quality battery facilities and personnel, along with our insights in what it takes to make a better electrode," says co-author Battaglia, program manager in the Advanced Energy Technology department of Berkeley Lab's Environmental and Energy Technologies Division. "In return, we have an outlet for getting these requirements out to scientists developing the next generation of materials."

Explore further: Thinnest feasible nano-membrane produced

More information: Energy Environ. Sci., 2011, Advance Article DOI: 10.1039/C1EE01592C

Provided by DOE/Lawrence Berkeley National Laboratory

5 /5 (5 votes)

Related Stories

Producing graphene layers using crystallization

Mar 02, 2010

(PhysOrg.com) -- Ever since it's relatively recent discovery, graphene has generated a great deal of interest. Graphene is extracted from graphite in many cases, and consists of a sheet of carbon atoms bound together in a ...

The noise about graphene

Oct 15, 2010

(PhysOrg.com) -- In last week’s announcement of the Nobel Prize in Physics, the Royal Swedish Academy of Sciences lauded graphene’s "exceptional properties that originate from the remarkable world ...

Turning down the noise in graphene

Aug 06, 2010

(PhysOrg.com) -- Graphene is a two-dimensional crystalline sheet of carbon atoms - meaning it is only one atom thick - through which electrons can race at nearly the speed of light - 100 times faster than ...

Recommended for you

Thinnest feasible nano-membrane produced

9 hours ago

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Wiring up carbon-based electronics

12 hours ago

Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered ...

Making 'bucky-balls' in spin-out's sights

Apr 16, 2014

(Phys.org) —A new Oxford spin-out firm is targeting the difficult challenge of manufacturing fullerenes, known as 'bucky-balls' because of their spherical shape, a type of carbon nanomaterial which, like ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Scottingham
not rated yet Jul 27, 2011
I'm slightly confused by the picture. There is a Li ion being exchanged in the picture but the article doesn't mention how it works alongside the Li part of the battery.
aroc91
not rated yet Jul 27, 2011
disregard

More news stories

Thinnest feasible nano-membrane produced

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Wiring up carbon-based electronics

Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered ...

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Better thermal-imaging lens from waste sulfur

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...