Nav: Home

'Workhorse' lithium battery could be more powerful thanks to new design

June 25, 2018

ITHACA, N.Y. - Cornell University chemical engineering professor Lynden Archer believes there needs to be a battery technology "revolution" - and thinks that his lab has fired one of the first shots.

"What we have now [in lithium-ion battery technology] is actually at the limits of its capabilities," said Archer. "The lithium-ion battery, which has become the workhorse in powering new electronics technologies, operates at over 90 percent of its theoretical storage capacity. Minor engineering tweaks may lead to better batteries with more storage, but this is not a long-term solution."

"You need a kind of radical mindset change," he said, "and that means that you've got to almost start at the beginning."

Snehashis "Sne" Choudhury, Ph.D. '18, has come up with what Archer terms an "elegant" solution to a fundamental problem with rechargeable batteries that use energy-dense metallic lithium anodes: sometimes-catastrophic instability due to dendrites, which are spines of lithium that grow from the anode as ions travel back and forth through the electrolyte during charge and discharge cycles.

If the dendrite breaks through the separator and reaches the cathode, short-circuiting and fire can occur. Solid electrolytes have been shown to suppress dendrite growth mechanically, but at the expense of fast ion transport. Choudhury's solution: Confine dendrite growth by the structure of the electrolyte itself, which can be controlled chemically.

Using a reaction procedure the Archer group introduced in 2015, they employ "cross-linked hairy nanoparticles" - a graft of silica nanoparticles and a functionalized polymer (polypropylene oxide) - to create a porous electrolyte that effectively lengthens the route ions must take to travel from the anode to the cathode and back, dramatically increasing the life of the anode.

Their paper, "Confining Electrodeposition of Metals in Structured Electrolytes," was published in Proceedings of the National Academy of Sciences. Choudhury and Dylan Vu - a rising junior majoring in chemical engineering - are co-first authors.

Choudhury, who is headed to Stanford University for his postdoctoral work, also devised a method for direct visualization of the inner workings of their experimental battery. The group confirmed theoretical predictions about dendrite growth with Choudhury's device.

"This is something I've wanted to do for, I guess, three Ph.D. students' lifetimes," said Archer, who's been at Cornell since 2000, with a laugh. "What Sne was able to do was design a cell that allowed us to, very elegantly, visualize what is occurring at the lithium-metal interface, giving us now the ability to go beyond theoretical predictions."

Another novelty of this work, Archer said, is "overturning something of a canon" in battery science. It's long been held that, in order to suppress dendrite growth, the separator inside the battery must be stronger than the metal it is trying to suppress, but Choudhury's porous polymer separator - with average pore sizes below 500 nanometers - were shown to arrest the growth.
-end-
The work was supported by a grant from the National Science Foundation.

Cornell University has television, ISDN and dedicated Skype/Google+ Hangout studios available for media interviews.

Cornell University

Related Batteries Articles:

A seaweed derivative could be just what lithium-sulfur batteries need
Lithium-sulfur batteries have great potential as a low-cost, high-energy, energy source for both vehicle and grid applications.
Batteries from scrap metal
Chinese scientists have made good use of waste while finding an innovative solution to a technical problem by transforming rusty stainless steel mesh into electrodes with outstanding electrochemical properties that make them ideal for potassium-ion batteries.
Better cathode materials for lithium-sulphur-batteries
A team at the Helmholtz-Zentrum Berlin (HZB) has for the first time fabricated a nanomaterial made from nanoparticles of a titanium oxide compound (Ti4O7) that is characterized by an extremely large surface area, and tested it as a cathode material in lithium-sulphur batteries.
Bright future for self-charging batteries
Who hasn't lived through the frustrating experience of being without a phone after forgetting to recharge it?
Making batteries from waste glass bottles
Researchers at the University of California, Riverside's Bourns College of Engineering have used waste glass bottles and a low-cost chemical process to create nanosilicon anodes for high-performance lithium-ion batteries.
Batteries -- quick coatings
Scientists at Oak Ridge National Laboratory are using the precision of an electron beam to instantly adhere cathode coatings for lithium-ion batteries -- a leap in efficiency that saves energy, reduces production and capital costs, and eliminates the use of toxic solvents.
Lighter, more efficient, safer lithium-ion batteries
Researchers from Universidad Carlos III de Madrid and the Council for Scientific Research (initialed CSIC in Spanish) have patented a method for making new ceramic electrodes for lithium-ion batteries that are more efficient, cheaper, more resistant and safer than conventional batteries.
Clarifying how lithium ions ferry around in rechargeable batteries
IBS scientists observe the real-time ultrafast bonding of lithium ions with the solvents, in the same process that happens during charging and discharging of lithium batteries, and conclude that a new theory is needed.
A new approach to improving lithium-sulfur batteries
Researchers from the University of Delaware and China's Northwestern Polytechnical University, Shenzhen University and Hong Kong Polytechnic University have demonstrated a new polysulfide entrapping strategy that greatly improves the cycle stability of Li-S batteries.
Looking for the next leap in rechargeable batteries
USC researchers may have just found a solution for one of the biggest stumbling blocks to the next wave of rechargeable batteries -- small enough for cellphones and powerful enough for cars.

Related Batteries Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Changing The World
What does it take to change the world for the better? This hour, TED speakers explore ideas on activism—what motivates it, why it matters, and how each of us can make a difference. Guests include civil rights activist Ruby Sales, labor leader and civil rights activist Dolores Huerta, author Jeremy Heimans, "craftivist" Sarah Corbett, and designer and futurist Angela Oguntala.
Now Playing: Science for the People

#521 The Curious Life of Krill
Krill may be one of the most abundant forms of life on our planet... but it turns out we don't know that much about them. For a create that underpins a massive ocean ecosystem and lives in our oceans in massive numbers, they're surprisingly difficult to study. We sit down and shine some light on these underappreciated crustaceans with Stephen Nicol, Adjunct Professor at the University of Tasmania, Scientific Advisor to the Association of Responsible Krill Harvesting Companies, and author of the book "The Curious Life of Krill: A Conservation Story from the Bottom of the World".