Researchers create new battery with 10x the juice

Engineers from Northwestern University create new battery that will give your smartphone longer life

For those of you who chronically forget to charge your smartphone, laptop, etc., modern science may have the answer. Chemistry researchers at Northwestern University have made an exciting breakthrough, developing a lithium-ion battery with a much longer life than current technology. 

“We have found a way to extend a new lithium-ion battery’s charge life by 10 times,” said Harold H. Kung, Northwestern professor of chemical and biological engineering, in a statement by the university.  “Even after 150 charges, which would be one year or more of operation, the battery is still five times more effective than lithium-ion batteries on the market today.”

Kung was lead author on the paper containing the relevant research, "In-Plane Vacancy-Enabled High-Power Si-Graphene Composite Electrode for Lithium-Ion Batteries," published in the journal Advanced Energy Materials. His research team has indicated that their new batteries could be on the marketplace within the next 3-5 years.

This breakthrough has improved both battery charge rate and capacity. Lithium-ion batteries are charged in the movement of electrons from an electrolyte to an anode. Current batteries use graphene anodes, though silicon has been determined as a superior medium. The problem is that Silicon tends to contract and expand in the charging process, something called "fragmentation."

These new batteries have clusters of silicon in between graphene sheets, which Kung, et al. claim eliminates or greatly reduces fragmentation, while still utilizing silicon's unique properties. The research team also equipped these graphene sheets with what the researchers called "in-plane defects," or tiny holes to speed up the charging rate, by creating electron short-cuts to the anode.

“Now we almost have the best of both worlds,” Kung said in his statement. “We have much higher energy density because of the silicon, and the sandwiching reduces the capacity loss caused by the silicon expanding and contracting.”

Kung's research may have other applications that reach into larger energy concerns, such as the use of solar energy.

"I can think of two ideas [concerning] solar energy capture that are related to batteries," said Kung to VatorNews. "[First], Batteries of significantly better rate capability and capacity should help achieve more widespread use of solar energy for electricity production, since there is a mismatch of sunlight availability and electricity usage.

"[Second], these flexible, thin-film electrodes may be suitable for direct solar batteries, which are batteries rechargeable directly with sunlight. The thin-film configuration is suitable for solar absorption."

Next up on Kung's agenda: shifting focus from battery anodes to the cathodes, as well as developing a system where batteries will automatically shut off at high temperatures. This development could lead to safety innovations in car battery applications.

In addition to holding a professorship at Northwestern, Kung is also a Dorothy Ann and Clarence L. Ver Steeg Distinguished Research Fellow. Kung's research is funded by the Energy Frontier Research Center program of the U.S. Department of Energy.