What good are clean-energy cars if the batteries that power them catch fire?
That is the problem a UNLV research team will try to unravel under a three-year, $2.5 million grant that Energy Secretary Steven Chu announced Wednesday with funding for 65 other clean-energy projects in 23 states.
The projects are part of the Obama administration's approach to resolving the nation's energy challenges through cutting-edge technologies that hold promise for success but are not far enough along for private-sector investment, Department of Energy officials said.
DOE's Advanced Research Projects Agency-Energy will award $130 million for 66 projects.
They include demonstrating that lasers can be used to drill through rock to anchor wind turbines; developing white roofing materials to reflect visible sunlight and infrared and ultraviolet light back into space, thus reducing air conditioning costs; and developing high-performance magnets that use less rare earth materials and reduce costs for wind turbine generators and electric vehicle motors.
"We're looking for things that could change the game," Chu said in a conference call with reporters.
The task for the team from the University of Nevada, Las Vegas will be to develop a fire-resistant solid electrolyte for vehicle batteries because the flammable, corrosive liquid used in today's lithium-ion batteries can catch fire from impact, overheating and overcharging.
The solution is to develop a solid, lithium-rich crystalline medium that would be similar to a "swamp with a trench in it" to provide a safe channel for ions to generate an electric current, said UNLV physics and astronomy professor Yusheng Zhao, the team leader.
"In order to make the lithium-ion battery perform safely, people have been trying to use a solid electrolyte. So this way even with impact, it should not catch fire," Zhao said from Boston, where he is attending a scientific conference.
The project expands on research he conducted at the Los Alamos National Laboratory in New Mexico.
It involves growing lithium-rich crystals with vacant spots that line up to form "trenches" for channeling ions from the surrounding lithium-rich "swamp."
Typical lithium-ion rechargeable batteries use a liquid or gel electrolyte consisting of a solvent containing lithium salt. The electrolyte conveys an electric current in the form of lithium ions when the battery discharges from the negative electrode to the positive electrode.
An outside electrical source is used to recharge the battery by reversing the current and sending lithium ions back to the negative electrode.
Lithium is a soft metal that is silver-white in color. It is flammable and corrodes in moist air. Much of it that is used by battery manufacturers is extracted from brine deposits in South America, but speculators are eyeing dry lake beds in Nevada as a potential source, said Jim Hodge, chief technical officer for Henderson-based K2 Energy Solutions, which produces lithium-ion batteries.
Hodge said lithium is fast becoming a material of high demand because lithium-ion batteries have longer life cycles than lead-acid batteries and weigh four times less than lead-acid batteries with the same power capacity.
The weight factor and longevity is why the military is interested to converting to lithium-ion batteries, he said. But the drawback is that the organic liquid electrolyte can leak out and catch fire if they are damaged.
That is where Zhao's team at UNLV comes in, with colleagues at the Los Alamos lab and some from Texas.
Their goal will be to make this "superionic solid electrolyte" material at room temperature. Once that is achieved, a lithium solid battery will be available for testing and marketing , Zhao said.
Chu said the $2.5 million grant will be used to try to develop a research program that will result in laboratory production of a solid, rocklike material called "lithium-rich anti-perovskite" for a working battery in three years. The battery then would be tested to demonstrate that it works as designed, with K2 Energy Solutions being a prospective outlet for advancing the technology.
Contact reporter Keith Rogers at firstname.lastname@example.org or 702-383-0308.