A snapshot of the inside of the Volkwagen Golf researchers outfitted with battery modules for their planned cross-country trip.
Photo courtesy of UC San Diego
Undergraduate students at UC San Diego work on the battery module system.
Photo courtesy of UC San Diego
Graduate student Xin Zhao at work on control algorithms.
Photo courtesy of UC San Diego
Imagine being able to switch out the batteries in electric cars just like you switch out batteries in a photo camera or flashlight. A team of engineers at the University of California, San Diego, are trying to accomplish just that, in partnership with a local San Diego engineering company.
Rather than swapping out the whole battery, which is cumbersome and requires large, heavy equipment, engineers plan to swap out and recharge smaller units within the battery, known as modules. They named the project Modular Battery Exchange and Active Management, or M-BEAM for short (http://www.modularexchange.com).
Engineers have already purchased and converted a car, a 2002 four-door Volkswagen Golf. They also built all the modules for one of the two battery packs they plan to use and are now looking for sponsors for their project, including companies or individuals that appreciate the benefits of having small exchangeable battery modules in an electric vehicle.
“This is a game-changing technology,” said Lou Shrinkle, an electrical engineer who is one of the major sponsors of the project. “This idea may seem straightforward, but there were some tough technical challenges that we had to solve to make this system robust and practical.”
Swapping battery modules could also have far-reaching implications for mobile and decentralized electrical energy storage systems such as solar backup and portable generators. The technology can make energy storage more configurable, promote safety, simplify maintenance and eventually eliminate the use of fossil fuels for these applications, Shrinkle pointed out
Engineers not only believe that their approach is viable, but also plan to prove it. They will embark on a cross-country trip with a car powered by the removable, rechargeable M-BEAM battery modules. They plan to drive from coast to coast only taking breaks that are a few minutes long to swap out the modules that will be recharged in a chase vehicle. They believe they can drive from San Diego to the coast of South Carolina less than 60 hours—without going over the speed limit.
“This requires a completely different way of thinking on battery management,” said Raymond de Callafon, a mechanical engineering professor at the Jacobs School of Engineering at UC San Diego. “Electric storage capacity is increased when modules are connected in parallel, but this requires a careful control of stray currents between modules.”
Algorithms for charge estimation and current control
A team led by de Callafon is designing the algorithms for charge estimation and current control, implemented in an embedded system that is part of the battery management system for each module. The algorithms will be able to handle battery modules with different charge levels, chemistry, age and condition and keep the modules working together uniformly. The team has published their findings in a recent paper titled “Current Scheduling for Parallel Buck Regulated Battery Modules” in the IFAC World Congress held in Cape Town, South Africa in August, 2014.
Xin Zhao, the graduate student that is part of the team, explains in the paper that rechargeable, removable battery modules in electric cars would solve numerous problems. Being able to simply swap and combine battery modules would eliminate range anxiety and extend the range that cars are able to travel indefinitely — the average range of most affordable electric vehicles is about 70 to 100 miles per charge. Batteries themselves take 4 to 12 hours to charge with conventional power sources. Newer, fast-charge technology still takes about 30 minutes and involves running very high power through batteries, shortening their lifetime and reducing safety.
What would change
The team says there are many advantages in their approach of recharging and swapping out smaller modules within a large battery. The approach allows for a separation between the purchase of an electric vehicle and its battery pack. The price of electric vehicles would drop by about $10,000 if removable battery modules are leased rather than built into an electric vehicle.
Also, as of today, more than 40 percent of people living in cities don’t have access to wall outlets to charge their electrical vehicles at the curb or in a garage. Exchangeable modules could be taken out of the car and recharged at home. Exchangeable modules would also allow an expanded mix of chemistries and energy densities lowering costs and improving range. Removable batteries could even be brought into the home to be charged and be part of an electricity back-up system.
Challenges and future work
But there are challenges. At 20 to 30 lbs. each, the modules are not exactly light-weight. Researchers believe that as battery technology matures, module size will shrink to about the size of a tissue box, weighing less than 10 lbs. The ability to swap battery modules from an electric vehicle allows easy adaptation of such new battery technology.
A battery system based on exchangeable modules would also need an infrastructure that allows users to lease or purchase the rechargeable modules. Businesses that either charge the modules or rent out pre-charged modules would also need to be available throughout the country. But engineers point out that electric vehicle charging stations, especially fast-charge stations, are not widely available either. Exchange stations could easily be gradually deployed. Imagine simply exchanging your modules at the local gas station that charges them for you, much like you can fill up propane tanks today.
Electric shock can also be a risk during removal and replacement of high voltage modules. The battery management system developed by the research team ensures that the output voltage of the battery is equal to zero unless the battery is in the vehicle and enabled by a key switch. Modules are configured to exhibit only safe low voltages even when fully compromised during and after a crash and have built-in solid-state switches to handle a short circuit condition.
Professor de Callafon is excited about the design and testing of the battery modules using a cross-country trip with an electric vehicle. “The cross-country trip will generate a wealth of scientific data on the performance of the battery modules we have designed.” The team hopes that the cross-country trip will change the way we think about mobile energy storage for electric transportation.
This article (9-16-14) is an EV News Report repost, credit: UC San Diego.
Electric Vehicle Association of Greater Washington, D.C. At the 2014 Washington Auto Show, the Electric Vehicle Association of Greater Washington, D.C., displayed some of its members’ electric vehicles, including this Porsche that is fitted with solar panels. Photo credit: Sarah Gerrity, DOE
Introduced more than 100 years ago, electric cars are seeing a rise in popularity today for many of the same reasons they were first popular.
Whether it’s a hybrid, plug-in hybrid or all-electric, the demand for electric drive vehicles will continue to climb as prices drop and consumers look for ways to save money at the pump. Currently more than 3 percent of new vehicle sales, electric vehicle sales could grow to nearly 7 percent — or 6.6 million per year — worldwide by 2020, according to a report by Navigant Research.
With this growing interest in electric vehicles, we are taking a look at where this technology has been and where it’s going. Travel back in time with us as we explore the history of the electric car.
The birth of the electric vehicle
It’s hard to pinpoint the invention of the electric car to one inventor or country. Instead it was a series of breakthroughs — from the battery to the electric motor — in the 1800s that led to the first electric vehicle on the road.
In the early part of the century, innovators in Hungary, the Netherlands and the United States — including a blacksmith from Vermont — began toying with the concept of a battery-powered vehicle and created some of the first small-scale electric cars. And while Robert Anderson, a British inventor, developed the first crude electric carriage around this same time, it wasn’t until the second half of the 19th century that French and English inventors built some of the first practical electric cars.
Here in the U.S., the first successful electric car made its debut around 1890 thanks to William Morrison, a chemist who lived in Des Moines, Iowa. His six-passenger vehicle capable of a top speed of 14 miles per hour was little more than an electrified wagon, but it helped spark interest in electric vehicles.
Over the next few years, electric vehicles from different automakers began popping up across the U.S. New York City even had a fleet of more than 60 electric taxis. By 1900, electric cars were at their heyday, accounting for around a third of all vehicles on the road. During the next 10 years, they continued to show strong sales.
The early rise and fall of the electric car
To understand the popularity of electric vehicles circa 1900, it is also important to understand the development of the personal vehicle and the other options available. At the turn of the 20th century, the horse was still the primary mode of transportation. But as Americans became more prosperous, they turned to the newly invented motor vehicle — available in steam, gasoline or electric versions — to get around.
Steam was a tried and true energy source, having proved reliable for powering factories and trains. Some of the first self-propelled vehicles in the late 1700s relied on steam; yet it took until the 1870s for the technology to take hold in cars. Part of this is because steam wasn’t very practical for personal vehicles. Steam vehicles required long startup times — sometimes up to 45 minutes in the cold — and would need to be refilled with water, limiting their range.
As electric vehicles came onto the market, so did a new type of vehicle — the gasoline-powered car — thanks to improvements to the internal combustion engine in the 1800s. While gasoline cars had promise, they weren’t without their faults. They required a lot of manual effort to drive — changing gears was no easy task and they needed to be started with a hand crank, making them difficult for some to operate. They were also noisy, and their exhaust was unpleasant.
Electric cars didn’t have any of the issues associated with steam or gasoline. They were quiet, easy to drive and didn’t emit a smelly pollutant like the other cars of the time. Electric cars quickly became popular with urban residents — especially women. They were perfect for short trips around the city, and poor road conditions outside cities meant few cars of any type could venture farther. As more people gained access to electricity in the 1910s, it became easier to charge electric cars, adding to their popularity with all walks of life (including some of the “best known and prominent makers of gasoline cars” as a 1911 New York Times article pointed out).
Many innovators at the time took note of the electric vehicle’s high demand, exploring ways to improve the technology. For example, Ferdinand Porsche, founder of the sports car company by the same name, developed an electric car called the P1 in 1898. Around the same time, he created the world’s first hybrid electric car — a vehicle that is powered by electricity and a gas engine. Thomas Edison, one of the world’s most prolific inventors, thought electric vehicles were the superior technology and worked to build a better electric vehicle battery. Even Henry Ford, who was friends with Edison, partnered with Edison to explore options for a low-cost electric car in 1914, according to Wired.
Yet, it was Henry Ford’s mass-produced Model T that dealt a blow to the electric car. Introduced in 1908, the Model T made gasoline-powered cars widely available and affordable. By 1912, the gasoline car cost only $650, while an electric roadster sold for $1,750. That same year, Charles Kettering introduced the electric starter, eliminating the need for the hand crank and giving rise to more gasoline-powered vehicle sales.
Other developments also contributed to the decline of the electric vehicle. By the 1920s, the U.S. had a better system of roads connecting cities, and Americans wanted to get out and explore. With the discovery of Texas crude oil, gas became cheap and readily available for rural Americans, and filling stations began popping up across the country. In comparison, very few Americans outside of cities had electricity at that time. In the end, electric vehicles all but disappeared by 1935.
Gas shortages spark interest in electric vehicles
Over the next 30 years or so, electric vehicles entered a sort of dark ages with little advancement in the technology. Cheap, abundant gasoline and continued improvement in the internal combustion engine hampered demand for alternative fuel vehicles.
Fast forward to the late 1960s and early 1970s. Soaring oil prices and gasoline shortages — peaking with the 1973 Arab Oil Embargo — created a growing interest in lowering the U.S.’s dependence on foreign oil and finding homegrown sources of fuel. Congress took note and passed the Electric and Hybrid Vehicle Research, Development, and Demonstration Act of 1976, authorizing the Energy Department to support research and development in electric and hybrid vehicles.
Around this same time, many big and small automakers began exploring options for alternative fuel vehicles, including electric cars. For example, General Motors developed a prototype for an urban electric car that it displayed at the Environmental Protection Agency’s First Symposium on Low Pollution Power Systems Development in 1973, and the American Motor Company produced electric delivery jeeps that the United States Postal Service used in a 1975 test program. Even NASA helped raise the profile of the electric vehicle when its electric Lunar rover became the first manned vehicle to drive on the moon in 1971.
Yet, the vehicles developed and produced in the 1970s still suffered from drawbacks compared to gasoline-powered cars. Electric vehicles during this time had limited performance — usually topping at speeds of 45 miles per hour — and their typical range was limited to 40 miles before needing to be recharged.
Environmental concern drives electric vehicles forward
Fast forward again — this time to the 1990s. In the 20 years since the long gas lines of the 1970s, interest in electric vehicles had mostly died down. But new federal and state regulations begin to change things. The passage of the 1990 Clean Air Act Amendment and the 1992 Energy Policy Act — plus new transportation emissions regulations issued by the California Air Resources Board — helped create a renewed interest in electric vehicles in the U.S.
During this time, automakers began modifying some of their popular vehicle models into electric vehicles. This meant that electric vehicles now achieved speeds and performance much closer to gasoline-powered vehicles, and many of them had a range of 60 miles.
One of the most well-known electric cars during this time was GM’s EV1, a car that was heavily featured in the 2006 documentary Who Killed the Electric Car? Instead of modifying an existing vehicle, GM designed and developed the EV1 from the ground up. With a range of 80 miles and the ability to accelerate from 0 to 50 miles per hour in just seven seconds, the EV1 quickly gained a cult following. But because of high production costs, the EV1 was never commercially viable, and GM discontinued it in 2001.
With a booming economy, a growing middle class and low gas prices in the late 1990s, many consumers didn’t worry about fuel-efficient vehicles. Even though there wasn’t much public attention to electric vehicles at this time, behind the scenes, scientists and engineers — supported by the Energy Department — were working to improve electric vehicle technology, including batteries.
A new beginning for electric cars
While all the starts and stops of the electric vehicle industry in the second half of the 20th century helped show the world the promise of the technology, the true revival of the electric vehicle didn’t happen until around the start of the 21st century. Depending on whom you ask, it was one of two events that sparked the interest we see today in electric vehicles.
The first turning point many have suggested was the introduction of the Toyota Prius. Released in Japan in 1997, the Prius became the world’s first mass-produced hybrid electric vehicle. In 2000, the Prius was released worldwide, and it became an instant success with celebrities, helping to raise the profile of the car. To make the Prius a reality, Toyota used a nickel metal hydride battery — a technology that was supported by the Energy Department’s research. Since then, rising gasoline prices and growing concern about carbon pollution have helped make the Prius the best-selling hybrid worldwide during the past decade.
(Historical footnote: Before the Prius could be introduced in the U.S., Honda released the Insight hybrid in 1999, making it the first hybrid sold in the U.S. since the early 1900s.)
The other event that helped reshape electric vehicles was the announcement in 2006 that a small Silicon Valley startup, Tesla Motors, would start producing a luxury electric sports car that could go more than 200 miles on a single charge. In 2010, Tesla received at $465 million loan from the Department of Energy’s Loan Programs Office — a loan that Tesla repaid a full nine years early — to establish a manufacturing facility in California. In the short time since then, Tesla has won wide acclaim for its cars and has become the largest auto industry employer in California.
Tesla’s announcement and subsequent success spurred many big automakers to accelerate work on their own electric vehicles. In late 2010, the Chevy Volt and the Nissan LEAF were released in the U.S. market. The first commercially available plug-in hybrid, the Volt has a gasoline engine that supplements its electric drive once the battery is depleted, allowing consumers to drive on electric for most trips and gasoline to extend the vehicle’s range. In comparison, the LEAF is an all-electric vehicle (often called a battery-electric vehicle, an electric vehicle or just an EV for short), meaning it is only powered by an electric motor.
Over the next few years, other automakers began rolling out electric vehicles in the U.S.; yet, consumers were still faced with one of the early problems of the electric vehicle — where to charge their vehicles on the go. Through the Recovery Act, the Energy Department invested more than $115 million to help build a nation-wide charging infrastructure, installing more than 18,000 residential, commercial and public chargers across the country. Automakers and other private businesses also installed their own chargers at key locations in the U.S., bringing today’s total of public electric vehicle chargers to more than 8,000 different locations with more than 20,000 charging outlets.
At the same time, new battery technology — supported by the Energy Department’s Vehicle Technologies Office — began hitting the market, helping to improve a plug-in electric vehicle’s range. In addition to the battery technology in nearly all of the first generation hybrids, the Department’s research also helped develop the lithium-ion battery technology used in the Volt. More recently, the Department’s investment in battery research and development has helped cut electric vehicle battery costs by 50 percent in the last four years, while simultaneously improving the vehicle batteries’ performance (meaning their power, energy and durability). This in turn has helped lower the costs of electric vehicles, making them more affordable for consumers.
Consumers now have more choices than ever when it comes to buying an electric vehicle. Today, there are 23 plug-in electric and 36 hybrid models available in a variety of sizes — from the two-passenger Smart ED to the midsized Ford C-Max Energi to the BMW i3 luxury SUV. As gasoline prices continue to rise and the prices on electric vehicles continue to drop, electric vehicles are gaining in popularity — with more than 234,000 plug-in electric vehicles and 3.3 million hybrids on the road in the U.S. today.
The future of electric cars
It’s hard to tell where the future will take electric vehicles, but it’s clear they hold a lot of potential for creating a more sustainable future. If we transitioned all the light-duty vehicles in the U.S. to hybrids or plug-in electric vehicles using our current technology mix, we could reduce our dependence on foreign oil by 30-60 percent, while lowering the carbon pollution from the transportation sector by as much as 20 percent.
To help reach these emissions savings, in 2012 President Obama launched the EV Everywhere Grand Challenge — an Energy Department initiative that brings together America’s best and brightest scientists, engineers and businesses to make plug-in electric vehicles more as affordable as today’s gasoline-powered vehicles by 2022. On the battery front, the Department’s Joint Center for Energy Storage Research at Argonne National Laboratory is working to overcome the biggest scientific and technical barriers that prevent large-scale improvements of batteries.
And the Department’s Advanced Research Projects Agency-Energy (ARPA-E) is advancing game-changing technologies that could alter how we think of electric vehicles. From investing in new types of batteries that could go further on a single charge to cost-effective alternatives to materials critical to electric motors, ARPA-E’s projects could transform electric vehicles.
In the end, only time will tell what road electric vehicles will take in the future.
WASHINGTON—As part of the Obama Administration’s efforts to reduce dependence on foreign oil and transition to a clean energy economy, the Energy Department today announced more than $55 million for 31 new projects to accelerate research and development of critical vehicle technologies that will improve fuel efficiency and reduce costs. These new projects are aimed at meeting the goals and objectives of the President’s EV Everywhere Grand Challenge, as well as improvements in other vehicle technologies such as powertrains, fuel, tires and auxiliary systems.
Launched in 2012, the EV Everywhere Grand Challenge seeks to make the U.S. automotive industry the first to produce plug-in electric vehicles (PEVs) that are as affordable and convenient as today’s gasoline-powered vehicles by 2022. In just the last several years, significant cost reductions and improvements in vehicle performance have had a dramatic impact on the U.S. automotive market. PEV sales continue to grow – sales in the first six months of 2014 were over 30 percent higher than the same period in 2013 – and the cost of battery technology has come down by over 60 percent since 2009.
Dr. Ernest Moniz Photo courtesy of DOE
“Investments in the next generation of vehicle technologies will both strengthen our economy and lead to a more fuel efficient, clean energy future,” said Secretary Ernest Moniz. “Improving vehicle efficiency is instrumental to establishing a 21st century transportation sector that creates jobs as well as protects future generations from harmful carbon emissions.”
Through the Advanced Vehicle Power Technology Alliance with the Energy Department, the Department of the Army is contributing an additional $3.7 million in co-funding to support projects focused on beyond lithium ion battery technologies and reducing friction and wear in the powertrain. The Army will also test and evaluate fuel-efficient tires resulting from projects at its facilities in Warren, Michigan.
“Partnering with the Energy Department, we are accelerating the development and deployment of cutting-edge technologies that will strengthen our military, economy, and energy security,” said Dr. Paul Rogers, director the U.S. Army Tank Automotive Research, Development and Engineering Center.
The selections announced today are under two major topic areas:
Critical Technologies to meet the EV Everywhere Grand Challenge: Nineteen projects are aimed at reducing the cost and improving the performance of key PEV components. This includes improving “beyond lithium ion technologies” that use higher energy storage materials, and developing and commercializing wide bandgap (WBG) semiconductors that offer significant advances in performance while reducing the price of vehicle power electronics. Other projects focus on advancing lightweight materials research to help electric vehicles increase their range and reduce battery needs, and developing advanced climate control technologies that reduce energy used for passenger comfort and increase the drive range of plug-in electric vehicles.
Fuel Efficiency Improvements in Passenger Vehicles and Commercial Trucks: Twelve projects are aimed at improvements including developing and demonstrating dual-fuel/bi-fuel technologies to reduce petroleum usage, accelerating growth in high-efficiency, cost-competitive engine and powertrain systems for light-duty vehicles, and accelerating the introduction of advanced lubricants and coatings to increase the efficiency of vehicles on the road today as well as future vehicles.
Read the full list of awardees.
The Energy Department’s Office of Energy Efficiency and Renewable Energy (EERE) accelerates development and facilitates deployment of energy efficiency and renewable energy technologies and market-based solutions that strengthen U.S. energy security, environmental quality, and economic vitality. The Vehicle Technologies Office funds research and development for energy efficient and environmentally-friendly vehicle technologies. To learn more about the program, please visit the Vehicle Technologies Office website.
This article is a repost, credit: Energy Department.
Photo courtesy of Idaho National Laboratory Wind Energy Program
Zinc Redox Flow Battery is Capable of 10,000 Cycles and 20 Plus Year Lifespan
What is the key to effectively utilizing alternative energy sources such as wind and solar? Safe and inexpensive storage. Today (9-17-13) the industry moves one giant step closer to solving the world’s energy limitation as ViZn Energy Systems, Inc. (formerly Zinc Air, Inc.) starts manufacturing its new Zinc Redox Flow Battery for customer pre-orders in the US and Europe.
ViZn’s Z20 160 kWh Zinc Redox Flow Battery is one of the most cost-effective and safe energy flow batteries on the market capable of providing scalable storage systems for the growing micro-grid markets and renewable integration.
“Right now more than 50 percent of all power generated is wasted before it ever gets to the end user,” explains Craig Wilkins, ViZn Energy Systems, Inc., President and CEO. “Storage batteries like our flow battery could help eliminate the billions of dollars of wasted energy each year. The impact this could have on the world is tremendous. It is understandable why the global smart grid market is expected to cumulatively surpass 400 billion dollars worldwide by 2020, according to a recent report by GTM Research.”
With more than fifteen years of research and intense product development cycles behind it, ViZn’s patented flow-battery technology breaks the cost/benefit threshold that is currently limiting widespread adoption of storage. Delivering a 1MW /2.5MWh battery system at lower pricing than current competition allows for more rapid industry adoption, wider commercial acceptance, and greater reduction of fossil fuel carbon emissions. ViZn’s Zinc Redox Flow Battery has overcome the key obstacles faced within the industry with an inventive use of materials and chemistry to provide a solution that is:
Cost Effective: ViZn implements low-cost chemistry, construction materials, and manufacturing processes that provide the foundation for a cost-effective system. In a micro-grid application, the ViZn battery system teamed with renewable generation can provide 20 percent annual returns over diesel-only generation.
Safe: ViZn’s battery is intrinsically safe with chemistry used in food-grade material that is non-flammable, non-explosive and non-toxic.
Scalable: ViZn’s Zinc Redox Flow Battery has the ability to scale to hundreds of Megawatts.
Reliable: ViZn’s Zinc Redox Flow Battery is estimated to have a 20 plus year lifespan.
Sustainable: ViZn’s Zinc Redox Flow Battery is composed of widely abundant and low cost materials.
“ViZn’s Zinc Redox technology has been designed to provide economical value by optimizing the balance between power and capacity. Our battery can provide power services such as renewable integration, regulation and ramping, while having enough energy capacity to economically provide load shifting and energy arbitrage,” said John Lowell, ViZn Energy Systems, Inc. COO and VP of Manufacturing and Product Development. “In addition, the 20 year life and safe operation of our battery separate us from other competing technologies.”
Availability
ViZn Energy Systems, Inc. is taking orders for the Z20 160 kWh Zinc Flow Batteries now with volume manufacturing ramping up in Q2 of 2014.
To learn more, visit http://www.viznenergy.com.
About ViZn Energy Systems, Inc.
ViZn Energy Systems, Inc., formerly Zinc Air, Inc., is comprised of a visionary team of scientists, engineers and business leaders that are passionate about creating and commercializing a revolutionary energy storage solution for the micro grid market. Founded in 2009 and based on ten previous years of research, ViZn is commercializing energy storage systems for mega-watt applications. The ViZn solution is safe, reliable, cost effective, and scalable to meet the needs of today’s ever changing energy landscape.
This article is a repost, (release 9-17-13) credit: ViZn Energy.
Professor Alan Weimer (back row, fifth from left) is shown with his 2013 CU-Boulder research group that involves postdoctoral researchers, research professionals, graduate students and undergraduates who make up the largest academic solar-thermal chemistry team in United States. (Image courtesy University of Colorado)
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.
This article is a repost (release 9-18-13), credit: University of Colorado.
