High-performance energy storage

Jul 03, 2007

North Carolina State University physicists have recently deduced a way to improve high-energy-density capacitors so that they can store up to seven times as much energy per unit volume than the common capacitor.

High performance capacitors would enable hybrid and electric cars with much greater acceleration, better and faster steering of rockets and spacecraft, better regeneration of electricity when using brakes in electric cars, and improved lasers, among many other electrical applications.

A capacitor is an energy storage device. Electrical energy is stored by a difference in charge between two metal surfaces. Unlike a battery, capacitors are designed to release their energy very quickly. They are used in electric power systems, hybrid cars, and all kinds of electronics.

The amount of energy that a capacitor can store depends on the insulating material in between the metal surfaces, called a dielectric. A polymer called PVDF has interested physicists as a possible high-performance dielectric. It exists in two forms, polarized or unpolarized. In either case, its structure is mostly frozen-in and changes only slightly when a capacitor is charged up. Mixing a second polymer called CTFE with PVDF results in a material with regions that can change their structure, enabling it to store and release unprecedented amounts of energy.

The team, led by Vivek Ranjan, concluded that a more ordered arrangement of the material inside the capacitor could further increase the energy storage of new high-performance capacitors, which already store energy four times more densely than capacitors used in industry. Their predictions of higher energy density capacitors are encouraging, but have yet to be experimentally tested.

Citation: Vivek Ranjan, L. Yu, M. Nardelli and J. Bernholc, Physical Review Letters (forthcoming article)

Source: American Physical Society

Explore further: Galaxy dust findings confound view of early Universe

add to favorites email to friend print save as pdf

Related Stories

Laser-induced graphene 'super' for electronics

Jan 14, 2015

Rice University scientists advanced their recent development of laser-induced graphene (LIG) by producing and testing stacked, three-dimensional supercapacitors, energy-storage devices that are important ...

Defects are perfect in laser-induced graphene

Dec 10, 2014

Researchers at Rice University have created flexible, patterned sheets of multilayer graphene from a cheap polymer by burning it with a computer-controlled laser. The process works in air at room temperature ...

Recommended for you

Galaxy dust findings confound view of early Universe

6 hours ago

What was the Universe like at the beginning of time? How did the Universe come to be the way it is today?—big questions and huge attention paid when scientists attempt answers. So was the early-universe ...

Seeking cracks in the Standard Model

Jan 30, 2015

In particle physics, it's our business to understand structure. I work on the Large Hadron Collider (LHC) and this machine lets us see and study the smallest structure of all; unimaginably tiny fundamental partic ...

Building the next generation of efficient computers

Jan 29, 2015

UConn researcher Bryan Huey has uncovered new information about the kinetic properties of multiferroic materials that could be a key breakthrough for scientists looking to create a new generation of low-energy, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.