CU News
News from the University of Colorado in Boulder.
CU scientists: New battery extends range and safety of electric-powered vehicles
Sep 22nd
A cutting-edge battery technology developed at the University of Colorado Boulder that could allow tomorrow’s electric vehicles to travel twice as far on a charge is now closer to becoming a commercial reality.
CU’s Technology Transfer Office has completed an agreement with Solid Power LLC—a CU-Boulder spinoff company founded by Se-Hee Lee and Conrad Stoldt, both associate professors of mechanical engineering—for the development and commercialization of an innovative solid-state rechargeable battery. Solid Power also was recently awarded a $3.4 million grant from the U.S. Department of Energy’s Advanced Research Projects Agency-Energy for the purpose of creating a battery that can improve electric vehicle driving range.
The rechargeable batteries that are standard in today’s electric vehicles—as well as in a host of consumer electronics, such as mobile phones and laptops—are lithium-ion batteries, which generate electricity when lithium ions move back and forth between electrodes in a liquid electrolyte solution.
Engineers and chemists have long known that using lithium metal as the anode in a rechargeable battery—as opposed to the conventional carbon materials that are used as the anode in conventional lithium-ion batteries—can dramatically increase its energy density. But using lithium metal, a highly reactive solid, in conjunction with a liquid electrolyte is extremely hazardous because it increases the chance of a thermal runaway reaction that can result in a fire or an explosion.
Today’s lithium-ion batteries require a bulky amount of devices to protect and cool the batteries. A fire onboard a Boeing Dreamliner in January that temporarily grounded the new class of plane was linked to its onboard lithium-ion battery.
Lee and Stoldt solved the safety concerns around using lithium metal by eliminating the liquid electrolyte. Instead, the pair built an entirely solid-state battery that uses a ceramic electrolyte to separate the lithium metal anode from the cathode. Because the solid-state battery is far safer, it requires less protective packaging, which in turn could reduce the weight of the battery system in electric vehicles and help extend their range.
Research into the development of solid-state batteries has gone on for a couple of decades, but it has been difficult to create a solid electrolyte that allowed the ions to pass through it as easily as a liquid electrolyte.
“The problem has always been that solid electrolytes had very poor performance making their use in rechargeable batteries impractical,” Stoldt said. “However, the last decade has seen a resurgence in the development of new solid electrolytes with ionic conductivities that rival their liquid counterparts.”
The critical innovation added by Lee and Stoldt that allows their solid-state lithium battery to out-perform standard lithium-ion batteries is the construction of the cathode, the part of the battery that attracts the positively charged lithium ions once they’re discharged from the lithium metal. Instead of using a solid mass of material, Lee and Stoldt created a “composite cathode,” essentially small particles of cathode material held together with solid electrolyte and infused with an additive that increases its electrical conductivity. This configuration allows ions and electrons to move more easily within the cathode.
“The real innovation is an all-solid composite cathode that is based upon an iron-sulfur chemistry that we developed at CU,” Stoldt said. “This new, low-cost chemistry has a capacity that’s nearly 10 times greater than state-of-the-art cathodes.”
Last year, Lee and Stoldt partnered with Douglas Campbell, a small-business and early-stage product development veteran, to spin out Solid Power.
“We’re very excited about the opportunity to achieve commercial success for the all solid-state rechargeable battery,” said Campbell, Solid Power’s president. “We’re actively engaging industrial commercial partners to assist in commercialization and expect to have prototype products ready for in-field testing within 18 to 24 months.” Important to the early success of the company has been its incubation within CU-Boulder’s College of Engineering and Applied Science’s applied energy storage research center, a part of the college’s energy systems and environmental sustainability initiative.
Solid Power is a member of Rocky Mountain Innosphere, a nonprofit technology incubator headquartered in Fort Collins, Colo., with a mission to accelerate the development and success of high-impact scientific and technology startup companies.
“We’re very excited to be working with Solid Power’s team to get them to the next level,” said Mike Freeman, Innosphere’s CEO. “This is a big deal to Colorado’s clean-tech space. Solid Power’s batteries will have a huge impact in the EV market, and they have a potential $20 billion market for their technology.”
Learn more about Solid Power at http://www.solidpowerbattery.com.
-CU-
CU: Rare western bumblebees netted on Colorado’s Front Range
Sep 3rd
A survey of bumblebee populations carried out largely by University of Colorado Boulder undergraduates in undisturbed patches of prairieland and in mountain meadows above campus has turned up more than 20 rare western bumblebees, known scientifically as Bombus occidentalis.
This is the fourth summer of a planned five-year survey in Boulder County, led by biologists Carol Kearns and Diana Oliveras, both of whom teach in CU-Boulder’s Baker Residential Academic Program. The survey team, which this summer included five undergraduates along with Oliveras and Kearns, has been hunting bumblebees at nine different locations spanning low, middle and high elevations.
The first western bumblebee was netted last year at one of the low-elevation plots, located at around 5,000 feet. The same plot also was visited frequently by Kearns and Oliveras during a more general survey of all pollinators between 2001 and 2005.
“For five years we sampled fairly intensely at this one site and never found anything,” Oliveras said. “Then all of a sudden, last year, we found several bees at that one site.”
The surveyors also found western bumblebees last year at a mid-elevation site of around 8,000 feet. In all, the team found nine western bumblebees in 2012: three queens and six workers.
Because insect populations are notoriously variable from year to year, Kearns and Oliveras wanted to find the bumblebees for a second year before announcing that the western bumblebee appeared to be returning to the Front Range. This year, the team has netted more than a dozen western bumblebees at four different locations, including the same low-elevation prairie plot and all three mid-elevation meadows. The distance between the sites means that the bumblebees are likely from separate colonies.
“These are sites that are fairly far away from each other, even as the crow flies,” Oliveras said. “Within a plot, if you’re going to be conservative, you can say that all the Bombus occidentalis arose from a single colony. But between plots, that’s quite a distance for them. They wouldn’t normally be traveling that far.”
The western bumblebee was once ubiquitous across the western portion of the United States and Canada, Oliveras and Kearns said. Its northern range encompassed all of Alaska, the Yukon Territory, British Columbia and western Alberta. Its southern boundaries extended as far south as Arizona and New Mexico. The bumblebee’s range also stretched from the Pacific Ocean eastward through North and South Dakota, Nebraska and Colorado. But beginning in the late 1990s, the western bumblebee became harder and harder to find.
“They have been disappearing rapidly across the West Coast, and there have been only occasional sightings in the Rocky Mountains,” Kearns said. “People have found a few bumblebees on the Western Slope of Colorado, but we were looking for them here and we weren’t finding any.”
Several factors have been implicated in the decline of the western bumblebee, according to Kearns and Oliveras. The biggest suspect is a non-native gut parasite that may have been transmitted from commercially raised bumblebee colonies. While parasites and other diseases can kill bees outright, anything that affects the bumblebees’ food supply or nesting sites also will affect their ability to survive. That means that habitat loss, pesticides, climate change and invasive plants and animals may be contributing to the losses in western bumblebee populations.
Earlier this summer, reports that the western bumblebee had been spotted in the Seattle area were confirmed by local biologists, indicating that the bumblebees could be making a broader comeback.
The wider goal of the ongoing bumblebee survey in Boulder County is to catalog all the types of bumblebees buzzing around the area and their population size. The team has catalogued a number of different species during the last four summers, including the mountain bumblebee, the Nevada bumblebee, the two-form bumblebee and the central bumblebee, among others.
“Our whole interest in bumblebees relates to the fact that pollinators are declining, but there is no abundance data for bumblebees in this area from the past,” Kearns said. “How do you tell if something is declining if there are no abundance data? So we decided we’d get out there and we’d find out what bumblebees are here and how many.”
Each year, Kearns and Oliveras have recruited undergraduate students to help them. This summer, the undergraduate researchers were Benjamin Bruffey, Sam Canter, Sarah Niemeyer, Zoe Praggastis and Cole Steinmetz.
To see a video about CU-Boulder’s bumblebee survey visit http://youtu.be/sKryBKX-nbU. For more information on the Baker Residential Academic Program visit http://bakerrap.colorado.edu/.
[includeme src=”http://c1n.tv/boulder/media/bouldersponsors.html” frameborder=”0″ width=”670″ height=”300″]
-CU-