Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Batteries Made From World’s Thinnest Material Could Power Tomorrow’s Electric Cars

27.08.2012
Engineering Researchers at Rensselaer Polytechnic Institute Use Intentionally Blemished Graphene Paper To Create Easy-To-Make, Quick-Charging Lithium-ion Battery With High Power Density

Engineering researchers at Rensselaer Polytechnic Institute made a sheet of paper from the world’s thinnest material, graphene, and then zapped the paper with a laser or camera flash to blemish it with countless cracks, pores, and other imperfections. The result is a graphene anode material that can be charged or discharged 10 times faster than conventional graphite anodes used in today’s lithium (Li)-ion batteries.


Rensselaer/Koratkar

Engineering researchers at Rensselaer Polytechnic Institute made a sheet of paper from the world’s thinnest material, graphene, and then zapped the paper with a laser or camera flash to blemish it with countless cracks, pores, and other imperfections. The result is a graphene anode material that can be charged or discharged 10 times faster than conventional graphite anodes used in lithium (Li)-ion batteries for today’s mobile phones, laptop and tablet computers, and even electric automobiles. The intentional imperfections are critical for the device’s ability to quickly accept or discharge large amounts of energy. As seen in this photo, the graphene paper displays both structural rigidity and integrity.

Rechargeable Li-ion batteries are the industry standard for mobile phones, laptop and tablet computers, electric cars, and a range of other devices. While Li-ion batteries have a high energy density and can store large amounts of energy, they suffer from a low power density and are unable to quickly accept or discharge energy. This low power density is why it takes about an hour to charge your mobile phone or laptop battery, and why electric automobile engines cannot rely on batteries alone and require a supercapacitor for high-power functions such as acceleration and braking.

The Rensselaer research team, led by nanomaterials expert Nikhil Koratkar, sought to solve this problem and create a new battery that could hold large amounts of energy but also quickly accept and release this energy. Such an innovation could alleviate the need for the complex pairing of Li-ion batteries and supercapacitors in electric cars, and lead to simpler, better-performing automotive engines based solely on high-energy, high-power Li-ion batteries. Koratkar and his team are confident their new battery, created by intentionally engineering defects in graphene, is a critical stepping stone on the path to realizing this grand goal. Such batteries could also significantly shorten the time it takes to charge portable electronic devices from phones and laptops to medical devices used by paramedics and first responders.

“Li-ion battery technology is magnificent, but truly hampered by its limited power density and its inability to quickly accept or discharge large amounts of energy. By using our defect-engineered graphene paper in the battery architecture, I think we can help overcome this limitation,” said Koratkar, the John A. Clark and Edward T. Crossan Professor of Engineering at Rensselaer. “We believe this discovery is ripe for commercialization, and can make a significant impact on the development of new batteries and electrical systems for electric automobiles and portable electronics applications.”

Results of the study were published this week by the journal ACS Nano in the paper “Photo-thermally reduced graphene as high power anodes for lithium ion batteries.” See the paper online at: http://pubs.acs.org/doi/abs/10.1021/nn303145j

Koratkar and his team started investigating graphene as a possible replacement for the graphite used as the anode material in today’s Li-ion batteries. Essentially a single layer of the graphite found commonly in our pencils or the charcoal we burn on our barbeques, graphene is an atom-thick sheet of carbon atoms arranged like a nanoscale chicken-wire fence. In previous studies, Li-ion batteries with graphite anodes exhibited good energy density but low power density, meaning they could not charge or discharge quickly. This slow charging and discharging was because lithium ions could only physically enter or exit the battery’s graphite anode from the edges, and slowly work their way across the length of the individual layers of graphene.

Koratkar’s solution was to use a known technique to create a large sheet of graphene oxide paper. This paper is about the thickness of a piece of everyday printer paper, and can be made nearly any size or shape. The research team then exposed some of the graphene oxide paper to a laser, and other samples of the paper were exposed to a simple flash from a digital camera. In both instances, the heat from the laser or photoflash literally caused mini-explosions throughout the paper, as the oxygen atoms in graphene oxide were violently expelled from the structure. The aftermath of this oxygen exodus was sheets of graphene pockmarked with countless cracks, pores, voids, and other blemishes. The pressure created by the escaping oxygen also prompted the graphene paper to expand five-fold in thickness, creating large voids between the individual graphene sheets.

The researchers quickly learned this damaged graphene paper performed remarkably well as an anode for a Li-ion battery. Whereas before the lithium ions slowly traversed the full length of graphene sheets to charge or discharge, the ions now used the cracks and pores as shortcuts to move quickly into or out of the graphene—greatly increasing the battery’s overall power density. Koratkar’s team demonstrated how their experimental anode material could charge or discharge 10 times faster than conventional anodes in Li-ion batteries without incurring a significant loss in its energy density. Despite the countless microscale pores, cracks, and voids that are ubiquitous throughout the structure, the graphene paper anode is remarkably robust, and continued to perform successfully even after more than 1,000 charge/discharge cycles. The high electrical conductivity of the graphene sheets also enabled efficient electron transport in the anode, which is another necessary property for high-power applications.

Koratkar said the process of making these new graphene paper anodes for Li-ion batteries can easily be scaled up to suit the needs of industry. The graphene paper can be made in essentially any size and shape, and the photo-thermal exposure by laser or camera flashes is an easy and inexpensive process to replicate. The researchers have filed for patent protection for their discovery. The next step for this research project is to pair the graphene anode material with a high-power cathode material to construct a full battery.

Along with Koratkar, co-authors of the paper are Rensselaer graduate students Rahul Mukherjee, Abhay Varghese Thomas, and Ajay Krishnamurthy, all of the Department of Mechanical, Aerospace, and Nuclear Engineering (MANE).

The study was funded by the National Science Foundation, and supported by Koratkar’s John A. Clark and Edward T.Crossan Endowed Chair Professorship at Rensselaer.

Koratkar is a professor in MANE and the Department of Materials Science and Engineering at Rensselaer. He is also a faculty member of the university’s Center for Future Energy Systems and the Rensselaer Nanotechnology Center.

For more information on the Koratkar’s research at Rensselaer, visit:

• Faculty Home Page
http://homepages.rpi.edu/~koratn/
• Nature Materials Study: Graphene “Invisible” to Water
http://news.rpi.edu/update.do?artcenterkey=2978
• Graphene Foam Detects Explosives, Emissions Better Than Today’s Gas Sensors
http://news.rpi.edu/update.do?artcenterkey=2950
• New Graphene Discovery Boosts Oil Exploration Efforts, Could Enable Self-Powered Microsensors

http://news.rpi.edu/update.do?artcenterkey=2900

• Water Could Hold Answer to Graphene Nanoelectronics
http://news.rpi.edu/update.do?artcenterkey=2783
• Graphene Outperforms Carbon Nanotubes for Creating Stronger Materials
http://news.rpi.edu/update.do?artcenterkey=2715
Contact
Michael Mullaney
Rensselaer Polytechnic Institute
Troy, NY
518-276-6161
mullam@rpi.edu
www.rpi.edu/news
Visit the Rensselaer research and discovery blog: http://approach.rpi.edu
Follow us on Twitter: www.twitter.com/RPInews

Michael Mullaney | Newswise Science News
Further information:
http://www.rpi.edu/news

More articles from Power and Electrical Engineering:

nachricht Scientists print sensors on gummi candy: creating microelectrode arrays on soft materials
21.06.2018 | Technische Universität München

nachricht Electron sandwich doubles thermoelectric performance
20.06.2018 | Hokkaido University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>