Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > New 'pomegranate-inspired' design solves problems for lithium-ion batteries

Left: Silicon nanoparticles are encased in carbon "yolk shells" and clustered like seeds in a pomegranate. Each cluster has a carbon rind that holds it together, conducts electricity and minimizes reactions with the battery's electrolyte that can degrade performance.

Right: Silicon nanoparticles swell during battery charging to completely fill their yolk shells; no space is wasted, and the shells stay intact.

Credit: Nian Liu, Zhenda Lu and Yi Cui/Stanford
Left: Silicon nanoparticles are encased in carbon "yolk shells" and clustered like seeds in a pomegranate. Each cluster has a carbon rind that holds it together, conducts electricity and minimizes reactions with the battery's electrolyte that can degrade performance.

Right: Silicon nanoparticles swell during battery charging to completely fill their yolk shells; no space is wasted, and the shells stay intact.

Credit: Nian Liu, Zhenda Lu and Yi Cui/Stanford

Abstract:
An electrode designed like a pomegranate - with silicon nanoparticles clustered like seeds in a tough carbon rind - overcomes several remaining obstacles to using silicon for a new generation of lithium-ion batteries, say its inventors at Stanford University and the Department of Energy's SLAC National Accelerator Laboratory.

New 'pomegranate-inspired' design solves problems for lithium-ion batteries

Stanford, CA | Posted on February 16th, 2014

"While a couple of challenges remain, this design brings us closer to using silicon anodes in smaller, lighter and more powerful batteries for products like cell phones, tablets and electric cars," said Yi Cui, an associate professor at Stanford and SLAC who led the research, reported today in Nature Nanotechnology.

"Experiments showed our pomegranate-inspired anode operates at 97 percent capacity even after 1,000 cycles of charging and discharging, which puts it well within the desired range for commercial operation."

The anode, or negative electrode, is where energy is stored when a battery charges. Silicon anodes could store 10 times more charge than the graphite anodes in today's rechargeable lithium-ion batteries, but they also have major drawbacks: The brittle silicon swells and falls apart during battery charging, and it reacts with the battery's electrolyte to form gunk that coats the anode and degrades its performance.

Over the past eight years, Cui's team has tackled the breakage problem by using silicon nanowires or nanoparticles that are too small to break into even smaller bits and encasing the nanoparticles in carbon "yolk shells" that give them room to swell and shrink during charging.

The new study builds on that work. Graduate student Nian Liu and postdoctoral researcher Zhenda Lu used a microemulsion technique common in the oil, paint and cosmetic industries to gather silicon yolk shells into clusters, and coated each cluster with a second, thicker layer of carbon. These carbon rinds hold the pomegranate clusters together and provide a sturdy highway for electrical currents.

And since each pomegranate cluster has just one-tenth the surface area of the individual particles inside it, a much smaller area is exposed to the electrolyte, thereby reducing the amount of gunk that forms to a manageable level.

Although the clusters are too small to see individually, together they form a fine black powder that can be used to coat a piece of foil and form an anode. Lab tests showed that pomegranate anodes worked well when made in the thickness required for commercial battery performance.

While these experiments show the technique works, Cui said, the team will have to solve two more problems to make it viable on a commercial scale: They need to simplify the process and find a cheaper source of silicon nanoparticles. One possible source is rice husks: They're unfit for human food, produced by the millions of tons and 20 percent silicon dioxide by weight. According to Liu, they could be transformed into pure silicon nanoparticles relatively easily, as his team recently described in Scientific Reports.

"To me it's very exciting to see how much progress we've made in the last seven or eight years," Cui said, "and how we have solved the problems one by one."

###

The research team also included Jie Zhao, Matthew T. McDowell, Hyun-Wook Lee and Wenting Zhao of Stanford. Cui is a member of the Stanford Institute for Materials and Energy Sciences, a joint SLAC/Stanford institute. The research was funded by the DOE Office of Energy Efficiency and Renewable Energy through the Batteries for Advanced Transportation Technologies program.

Citation: N. Liu, Z. Lu et al., Nature Nanotechnology, 16 February 2014 (10.1038/nnano.2014.6)

####

For more information, please click here

Contacts:
Andy Freeberg

650-926-4359

Copyright © DOE/SLAC National Accelerator Laboratory

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Laboratories

Shaping the Future of Nanocrystals: Berkeley Lab Researchers Obtain First Direct Observation of Facet Formation in Nanocubes August 21st, 2014

News and information

Shaping the Future of Nanocrystals: Berkeley Lab Researchers Obtain First Direct Observation of Facet Formation in Nanocubes August 21st, 2014

Hiden Release New Gas Analysis Catalogue August 21st, 2014

Wyatt Technology’s 24th International Light Scattering Colloquium to Highlight Developments in Applications and Characterization of Nanoparticles August 21st, 2014

Water window imaging opportunity: A new theoretical study elucidates mechanisms that could help in producing coherent radiations, ultimately promoting high-contrast imaging of biological samples August 21st, 2014

Govt.-Legislation/Regulation/Funding/Policy

Shaping the Future of Nanocrystals: Berkeley Lab Researchers Obtain First Direct Observation of Facet Formation in Nanocubes August 21st, 2014

Success in Intracellular Imaging of Cesium Distribution in Plants Used for Cesium Absorption August 19th, 2014

Electrical engineers take major step toward photonic circuits: Team invents non-metallic metamaterial that enables them to 'compress' and contain light August 19th, 2014

Promising Ferroelectric Materials Suffer From Unexpected Electric Polarizations: Brookhaven Lab scientists find surprising locked charge polarizations that impede performance in next-gen materials that could otherwise revolutionize data-driven devices August 18th, 2014

Discoveries

Shaping the Future of Nanocrystals: Berkeley Lab Researchers Obtain First Direct Observation of Facet Formation in Nanocubes August 21st, 2014

Water window imaging opportunity: A new theoretical study elucidates mechanisms that could help in producing coherent radiations, ultimately promoting high-contrast imaging of biological samples August 21st, 2014

Nanotechnology Helps Production of Super Adsorbent Polymers August 21st, 2014

Rice physicist emerges as leader in quantum materials research: Nevidomskyy wins both NSF CAREER Award and Cottrell Scholar Award August 20th, 2014

Announcements

Wyatt Technology’s 24th International Light Scattering Colloquium to Highlight Developments in Applications and Characterization of Nanoparticles August 21st, 2014

Ultra-short pulse lasers & Positioning August 21st, 2014

Malvern’s Dr Alan Rawle talks TLAs in plenary lecture at Particulate Systems Analysis conference August 21st, 2014

Water window imaging opportunity: A new theoretical study elucidates mechanisms that could help in producing coherent radiations, ultimately promoting high-contrast imaging of biological samples August 21st, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals

Shaping the Future of Nanocrystals: Berkeley Lab Researchers Obtain First Direct Observation of Facet Formation in Nanocubes August 21st, 2014

Water window imaging opportunity: A new theoretical study elucidates mechanisms that could help in producing coherent radiations, ultimately promoting high-contrast imaging of biological samples August 21st, 2014

Nanotechnology Helps Production of Super Adsorbent Polymers August 21st, 2014

Newly-Developed Nanobiosensor Quickly Diagnoses Cancer August 20th, 2014

Battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics

Graphene may be key to leap in supercapacitor performance August 20th, 2014

Could hemp nanosheets topple graphene for making the ideal supercapacitor? August 12th, 2014

Cylinder scanning system used in the ZylScan-System of the Breitmeier Messtechnik Company August 5th, 2014

Used-cigarette butts offer energy storage solution August 5th, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE