Porous Silicon as a Rechargeable Battery Anode Material
- 详细技术说明
- None
- *Abstract
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PorousSilicon as a Rechargeable Battery Anode Material
Challenge
The use of lithium-ionbatteries is widespread in consumer electronics, and their use in the defense,automotive, aerospace, and electrical utility industries is expanding. Despite this success, many of these marketsare demanding even higher energy density. These market signals range fromeveryone’s desire for longer-lasting batteries in cell phones and laptops, tothe desirability of a longer range between recharges for electric vehicles.
Lithium-ion batteries requirean anode material that uptakes lithium ions upon charging and can thenefficiently (and repeatedly) release those same lithium ions during discharge. The uptake capacity is directly related tothe amount of charge the battery can hold. Carbon-based materials currently serve as the anode material inrechargeable batteries, but the capacity limits are not sufficient to meethigher power requirements for applications in electric vehicles.
Silicon is often presented asan alternative anode material because of its extremely high theoretical capacityfor lithium ions. The use of silicon,however, is complicated by problems that result from its large expansion/contractionduring cycling, which typically results in extremely limited cycle life. A current challenge is the identification ofan optimal silicon composition and structure for use as anode materials thatleverages silicon’s lithium ion capacity, and can do this for hundreds (andultimately thousands) of cycles.
Solution
Thecurrent invention provides a method for fabricating porous silicon via an electrochemical etchingprocess. The resulting silicon materialretains the ability to take up a large number of lithium ions through numerouscharge/discharge cycles. Use of thismaterial leads to an increase in both capacity and cycle life over currentanode materials.
Theporous silicon layer can also be removed from the inactive bulk silicon substrate,resulting in higher capacities per sample weight. The use of a carbon binder allows the free-standing porous silicon layer to accommodate large volume changes uponlithiation while withstanding fracturing and maintaining a stable contact withthe current collector.
Benefitsand features
- Improved anode material for lithium-ion batteries
- Provides capacities of 3500 mAh/g for at least 60 cycles
- Imparts excellent cyclic stability
- Low cost, reproducible method for manufacturing anodes
MarketPotential / Applications
Thisinvention is of potential utility in the manufacture and use of lithium-ion batterytechnologies. The observed improvementsin capacity and cycle life augur well for the use of these materials indemanding battery applications such as those in the automotive and aerospacesectors.
Development and LicensingStatus
This technology is availablefor licensing from Rice University and Lockheed Martin. The technology was jointly developed and isjointly owned by Rice and Lockheed Martin.
Proof of principle has been establishedfor this technology.
ResearcherTeam
Michael S. Wong is a Professorin the Chemical and Biomolecular Engineering Department at RiceUniversity. He serves as AssociateEditor of the Journal of Nanomaterials,and his research interests encompass nanostructured materials, heterogeneouscatalysis, and bioengineering applications.
SibaniLisa Biswal is an Assistant Professor in the Department of Chemical andBiomolecular Engineering at Rice University. Her research focuses on understanding self-assembling systems andexploiting these systems in the development of novel materials.
StevenSinsabaugh is a Lockheed Martin Fellow, based in Lockheed Martin’s Akronfacility. He has over twenty five years experience in advanced materials,energy technologies and systems engineering.
TechnologyRelevant Papers and Web Links
A PCT application has been filedfor the use of this material as an anode material.
A provisional patentapplication has been filed for the liftoff procedure to generate an active, free-standing porous silicon layer.
http://sify.com/news/silicon-strategy-shows-promise-for-powerful-batteries-news-international-kkoo4fdjfci.html
Biswal Research Groupwebsite: http://www.ruf.rice.edu/%7Ebiswalab/index.htm
Wong Research Groupwebsite: http://www.ruf.rice.edu/~wonglab/index.html
Case# 2010-024
KeyWords:batteries, silicon, lithium-ion, anode, nanoporous
Inquiriesto:
Luba Pacala, lpacala@rice.edu, (713) 348-5590
Chance Rainwater, crainwater@rice.edu, (713) 348-4106
- 国家/地区
- 美国
