Lithium-Ion Batteries with New Electrode for Long Life

A new material has been developed to improve the energy storage capacity of batteries so that laptops, cellphones, electric cars and other mobile devices can be used for longer duration. This new material has been developed by Steven Arnold Klankowski, a doctoral candidate in chemistry, La Crescent, Minn., and is working under Jun Li, professor of chemistry.

He has developed materials to be used in the future lithium ion batteries.

"Additionally, lithium-ion batteries that can store energy and deliver power more rapidly will be a more viable alternative power source for vehicles and machines powered by alternative energy," Klankowski said. "For example, solar and wind-powered technologies could switch to the battery in the evening when there is a lack of wind or sunlight to produce energy."

"The battery market is moving very fast these days as everyone is trying to get an advantage for their electric vehicles and cellphones," said Klankowski, who also has a background in materials engineering. "As our devices get smarter, so must our methods to supply greater amounts of portable electrical energy to power these devices."

In order to create this material, he is developing and testing a high-performance nanostructure of silicon coated onto carbon nanofibers for the use as an electrode in lithium-ion batteries. The electrodes provide the battery greater charge capabilities and storage capacity. This design will replace the commercial electrodes that are made from simple carbon-based materials.

The new electrodes can now save up to 10 times the amount of energy the current electrodes can save that gives the battery 10-15 percent improvement in current battery technology.

"We're trying to go for higher energy capacity," Klankowski said. "To do that we're looking to store more energy per the electrode's size or mass, and if we can use that energy more quickly to make the battery like a capacitor. Batteries and capacitors are on opposite sides of the energy storage field. We'd like to move them both closer together."

According to U.S. Department of Energy's requirements, a battery must remain at 80 percent capacity after 300 charge-discharge cycles.

"A battery today tends to die after 400-500 cycles or three years," Klankowski said. "One of the things we'll want to improve on is that lasting performance. It won't be much of an advantage if your phone's battery can last for 36 hours for the first few months but then only two hours after that. With the progress we are seeing, I hope one day to drive from Manhattan to my folks' house in Minnesota on a single battery change."