Element 8 Member Meetings

Accredited Investors interested in membership in Element 8 are invited to participate as a guest in one meeting per year. If you’re interested in membership and would like to attend an upcoming meeting please email info@element8angels.com.


CleanTech Alliance Breakfast Series

The CleanTech Alliance Breakfast Series is your opportunity to rub elbows with distinguished cleantech executives from across Washington State, the Pacific Northwest and beyond. Presented by Perkins Coie, join 100 cleantech industry leaders for a monthly conversation featuring a tremendous lineup of distinguished speakers.

Each event is held on the second Wednesday of each month (7:30 a.m. to 9:00 a.m.) from September 2016 through May 2017 (except November, which is reserved for the CleanTech Alliance Annual Meeting).

For more information and to register for the events, visit the CleanTech Alliance website.



Science Highlights Readings

These downloadable new articles deal with clean energy topics. They have highlighted vocabulary and comprehension questions. They were originally circulated with our educators newsletter.

Printable solar cells reading

Nanocrystals reading

Lithium Ion Batteries reading

Energy Storage reading

UW Solar Researcher Named to Forbes 30 Under 30: Energy List


Dr. Daniel Kroupa’s research on perovskite thin films could create an efficiency breakthrough for solar photovoltaics when integrated with silicon panels


December 18, 2018


Dr. Daniel Kroupa, Washington Research Foundation Innovation Postdoctoral Fellow in Clean Energy, has been named to the Forbes “30 Under 30: Energy” list for 2019. Each year, Forbes magazine selects 30 rising leaders under 30 years old working on energy solutions. Kroupa, a member of chemistry professor Daniel Gamelin’s research group, is developing a method to increase sunlight-to-electricity conversion efficiency in solar photovoltaic (PV) cells. The technology works by printing an inexpensive perovskite-based coating onto the surface of standard silicon cells.

Dr. Daniel Kroupa, Washington Research Foundation Innovation Postdoctoral Fellow in Clean Energy


“The concept of a solar cell with two or more absorber layers is not new, but most commercial ‘multijunction’ PVs are expensive and limited to space-based applications,” explains Kroupa. “Our technology is unique because we’re working with a standard silicon cell as our primary PV layer, which is optically coupled to a second spectral conversion layer. Instead of developing a new device and manufacturing process, we’re making an inexpensive and simple upgrade to a mature design with just one additional step.”


Silicon PV cells exhibit poor conversion of high-energy blue and UV light to electricity, resulting in commercial cell efficiencies peaking near 24%. Attempting to engineer further gains in efficiency in silicon-only panels has generally provided diminishing returns on costs. Kroupa and his colleagues in the Gamelin lab have engineered perovskite coatings that absorb blue light and re-emit red light, releasing two low-energy photons for each high-energy photon collected. This phenomenon is known as “quantum cutting.” Not only does the layered design capture more of the sun’s spectrum, each photon that the silicon cell does absorb generates an electron that can be collected as electric current, so each blue photon can actually generate two electrons. Silicon panels with an additional quantum cutting spectral conversion layer could achieve an overall conversion efficiency up to 35%, with only a small increase in material and manufacturing cost.


“Better utilizing the solar spectrum and generating two electrons per high-energy photon would allow us to revolutionize silicon solar panel performance,” says Kroupa. “Now that we’ve developed the quantum cutting material, we can make significant strides for silicon-based PV at the characteristic low costs of metal-halide perovskites. In order to get to this point, we had to tune the perovskite chemical composition for optimal solar absorption while maintaining efficient quantum cutting. I’m fortunate to work with a great team in the Gamelin lab with broad expertise ranging from synthetic inorganic chemistry to advanced spectroscopic characterization, which has really accelerated the development of this exciting new class of solar absorber materials.”


Combined with the ability to build on a mature global manufacturing and distribution network for silicon PV, an increase to 35% efficiency could decrease the cost of solar PV-generated electricity by 10-30%. While stand-alone solar PV arrays are already competitive with natural gas and coal, the total cost of integrating these resources at scale remains high — energy storage and demand response solutions are needed to manage natural fluctuations in solar power. In particular, battery-based energy storage remains expensive. However, a significant decrease in PV prices could tip the scales in favor of the overall solar power package and promote rapid and widespread adoption within the market.


Kroupa and colleagues in the Gamelin group are establishing a company to commercialize quantum cutting technology for solar PV. They are currently developing their product at the Washington Clean Energy Testbeds. They have received support from the Washington Research Foundation and commercial solar panel manufacturers to perform pilot-scale testing and incorporate the perovskite coatings into existing manufacturing lines.


Kroupa joins the ranks of previous Forbes 30 Under 30: Energy honorees from the UW Clean Energy Institute: UW electrical and computer engineering professor Baosen Zhang, former UW chemistry postdoctoral fellow Dr. Giles Eperon, and former CEI Graduate Fellow in chemical engineering Dr, Matt Murbach.

Northwest Business Community Honors Washington Clean Energy Testbeds for Contributions to Local Energy Economy

Mike Pomfret at the Testbeds

Pomfret working on the facility’s roll-to-roll printer

Testbeds Managing Director Michael Pomfret Wins CleanTech Alliance & Northwest Environmental Business Council Energy Leadership Achievement Award


December 14, 2018


Two Northwest organizations representing the clean energy business community, the CleanTech Alliance and the Northwest Environmental Business Council (NEBC), have presented Michael Pomfret, managing director of the Washington Clean Energy Testbeds, with their 2018 Energy Leadership Achievement Award. The honor recognizes Pomfret’s work to accelerate the pace of cleantech commercialization in the region and beyond at the Testbeds. Pomfret oversaw the development of this open-access facility for prototyping, testing, and validating solar, battery, and system software/ hardware integration technologies, from construction, through opening in 2017, to tremendous first-year growth.


The award was announced at the Energy Leadership Summit, where 400 industry leaders and policymakers from across the Northwest convened to address current challenges and future opportunities for clean energy. The CleanTech Alliance and NEBC highlighted Pomfret’s accomplishments in not only establishing a state-of-the art facility to help users de-risk a cleantech concept, but also his work to create a supportive home for cleantech innovators to grow and attract investors to the region.


Mike Pomfret headshot

Washington Clean Energy Testbeds Managing Director Michael Pomfret

“This award from clean energy industry leaders is an acknowledgement that, in a very short time, we have created an important facility for cleantech innovation in the Northwest,” said Pomfret. “I’m honored to receive this award and to work on behalf of UW researchers and businesses accelerating a clean energy future. I’m also proud that the Testbeds have attracted companies globally to do work here, and both in-state and out-of-state companies have hired UW graduates to work at the facility to advance product development.”


Pomfret is an expert in energy materials and devices. He has a Ph.D. in chemistry and has worked on energy device development at the U.S. Naval Research Laboratory and for several cleantech startups.


“Mike has become an invaluable member of the Pacific Northwest cleantech community, and we can’t agree more that he deserves this recognition for his leadership at the Testbeds,” said Daniel Schwartz, director of the UW Clean Energy Institute (CEI), the organization that operates the Testbeds. “He has helped make the Testbeds into a dynamic realization of CEI’s goals, showing that partnerships between researchers and innovators in the private sector are a viable and fruitful pathway for cleantech.”


The Washington Clean Energy Testbeds serves a growing community of over 210 active users. This includes 29 cleantech startups, mid-size companies, and major corporations like Microsoft, as well as University of Washington (UW) scientists and engineers. Additionally, five of those 29 companies have operations based at the Testbeds where they use the facility’s instruments, trained experts, and networks to build their startups or develop new product lines. Testbeds users pay a per-use fee to use state-of-the-art instruments and access UW staff. External users retain all intellectual property developed at the Testbeds.


To best serve this mix of large and small enterprises and UW researchers, and to foster a vibrant cleantech ecosystem for the region, Pomfret has implemented several specialized programs at the Testbeds. The Entrepreneur-in-Residence (EIR) program, launched in partnership with UW CoMotion, is for users and others in the region interested in launching clean energy businesses. EIRs host regular public events and office hours to council established entrepreneurs and students. The Testbeds also host an Investor-in-Residence (IIR) program as a free consulting resource for local startups with E8, a cleantech-oriented angel investment group.


Leveraging UW’s clean energy research leadership and the Testbeds’ unique capabilities, Pomfret and Testbeds Technical Director and Professor J. Devin MacKenzie have helped local startups and cleantech companies win major research and development funding to advance their technologies. One current Testbeds user, MicroConnex in Snoqualmie, WA, recently secured a $1 million federally-funded research grant in partnership with UW researchers. Vesicus, an advanced materials startup, recently won $225,000 in Small Business Technology Transfer (STTR) funding to develop nanostructured thin films for lithium-ion batteries at the Testbeds. Membrion, a UW spin-out and Testbeds user, just completed a $2.23 million seed funding round.


About the Washington Clean Energy Testbeds
The University of Washington Clean Energy Institute (CEI) created the Washington Clean Energy Testbeds to accelerate the development, scale-up, and adoption of new technologies in solar harvesting, energy storage, and system integration. This open-access facility in Seattle, founded on the principle that users retain all intellectual property, offers customized training and use of instruments for fabricating prototypes, testing devices and modules, and integrating systems. The facility also houses meeting and office space where users from academia and business work and collaborate. Through special events, Entrepreneur-in-Residence and Investor-in-Residence programs, and community-sponsored networking opportunities, the Testbeds are an active gathering space for cleantech innovators and investors. wcet.washington.edu

Professor Brian B. Johnson Leads Department of Energy-Funded Research to Halve Cost of Solar Power Electronics

UW researchers partner with University of Colorado Boulder, National Renewable Energy Laboratory, and semiconductor manufacturer Wolfspeed to develop low-cost, high-efficiency inverters for solar photovoltaic power plants


November 14, 2018


The U.S. Department of Energy (DOE) has pledged $2.84M to a research team led by University of Washington (UW) electrical & computer engineering (ECE) professor Brian B. Johnson to lower the cost of power electronics in solar photovoltaic (PV) systems. The DOE’s long-term goal is to cut the cost of solar PV systems in half by 2030, down to $0.03/kWh over the lifetime of a system. The multi-institutional team includes UW ECE professor Daniel Kirschen, leading experts from the University of Colorado Boulder (CU), the National Renewable Energy Laboratory (NREL), and semiconductor manufacturer Wolfspeed.


Professor Brian Johnson Headshot

Brian B. Johnson, Washington Research Foundation Innovation Assistant Professor of Clean Energy and Electrical & Computer Engineering

Over a period of three years, Johnson’s team will develop ultra-low-cost electronics that convert direct current (DC) power from PV arrays into grid-compatible alternating current (AC) power. Unlike conventional DC-to-AC inverters used today which require a bulky and costly transformer to step up the low voltage that they produce, the proposed architecture is able to produce voltages up to the tens of thousands of volts using only electronics. The newly-proposed inverter will be assembled from many interconnected modular blocks where each block features a novel circuit design, state-of-the-art silicon carbide semiconductors, and advanced controllers. The resulting blocks are lightweight, self-contained, and autonomously-controlled, such that the overall system is modular and resilient to failures. This revolutionary design will reduce initial material and manufacturing costs by 30-50% compared to conventional inverters, and will also give higher energy efficiency due to a radically-new circuit design and the elimination of the external transformer.


“This project unites some of the latest advances in power electronics, wide-bandgap semiconductors, optimization, and controls into a concrete approach for PV system design,” said Johnson. “Along with the theoretical development of such a system, the hardware design phase will push the boundaries of what is physically possible and require us to think outside the box. Ultimately, the final prototypes must withstand extreme voltages and be amenable to low-cost manufacturing.”


In spring 2018, Johnson joined UW as a Washington Research Foundation Innovation Assistant Professor of Clean Energy and Electrical & Computer Engineering. Previously, he worked at NREL, focusing his research on next-generation controllers and energy conversion circuits for power grids and renewable energy systems. Clean power generators like solar PV installations are naturally much more distributed and volatile than centralized fossil fuel plants, so power engineers must create advanced, automated controls to maintain grid stability during surges in energy demand and generation. For solar PV, the supporting hardware, including inverters, wiring, and racks, often costs more than the modules themselves.


Daniel Kirschen

Daniel Kirschen, Close Professor of Electrical & Computer Engineering

Daniel Kirschen, Close Professor of Electrical & Computer Engineering, joined the DOE-backed team as an expert on the economics and optimization of power systems. He will play an active role in the design optimization phase, which aims to minimize system costs.


“While we obviously don’t have to pay for the energy that the sun provides, the cost of deploying PV systems remains high,” said Kirschen. “By optimizing the design of the power electronics, this project will make solar power more competitive.”


In the first year of the project, Johnson’s group will collaborate with CU’s Colorado Power Electronics Center (CoPEC) to develop the distributed control strategies, build a low-voltage testbed using six of the circuit-control blocks, and perform preliminary tests. In parallel, NREL will obtain market data and collaborate with both Johnson and Kirschen to design a cost-optimized system. The optimization process will reveal the design (device ratings, number of blocks, and other component values) which minimize overall cost.


The developed controllers and optimized system designs will be finalized in the second year, and the team will perform tests of a 2kV block with Wolfspeed’s latest devices. In the third year, Johnson’s group, the CU team, and NREL will construct a medium-voltage six-block system, which will be able to produce 13.2 kV of grid-compatible ac power with very high efficiency. The demonstration will take place at NREL, using their state-of-the-art Controllable Grid Interface to emulate a 13.2 kV grid interconnection. The cost-optimized marketing plan created by the UW-NREL partnership will be presented at a final project workshop with industry participants.


Revolutionary Printer for Sustainable Electronics Comes to Washington Clean Energy Testbeds

Joint Center for Deployment and Research in Earth Abundant Materials (JCDREAM) awarded $631K to Testbeds to install world’s first roll-to-roll inkjet printer for electronics with sub-micron features
UW professor J. Devin MacKenzie will use printer to develop cheap, sustainable alternative to rare-earth materials used in solar panels, displays, and touchscreens


November 6, 2018


The Joint Center for Deployment and Research in Earth Abundant Materials (JCDREAM), a Washington state research collaborative, has awarded $631K to University of Washington (UW) materials science & engineering and mechanical engineering associate professor J. Devin MacKenzie and the Washington Clean Energy Testbeds. MacKenzie will use the funds, which UW will supplement with $187K, to purchase and install an ultra-high-resolution electronics printer developed at SIJ Technology, Inc. and Japan’s National Institute of Advanced Industrial Science and Technology. When integrated with the existing roll-to-roll printer at the Testbeds, it will be the first system capable of high-throughput printing at sub-micron feature sizes. The printer will be available to academic and industry Testbeds users for research and development, prototyping, and commercial manufacturing. Advances in printed electronics will allow next-generation electronic devices to be sustainably manufactured with earth-abundant materials.


“We can’t wait to bring such a revolutionary device to the Testbeds thanks to JCDREAM,” said MacKenzie, Washington Research Foundation Professor of Clean Energy. “Our users will be able to print electronics using sustainable materials with finer control than ever before, and it will directly enable UW and industrial researchers to develop a sustainable alternative for a crucial element of flexible thin-film solar cells, displays and touch screens. This printer, the first of its kind in the world, can also be used to make improved sensors and higher power batteries.”


Devin Mackenzie and the roll-to-roll printer at the Testbeds

Professor J. Devin Mackenzie with the roll-to-roll printer at the Washington Clean Energy Testbeds.

Devices like solar cells, displays, and touchscreens often depend on rare earth and scarce materials that are transparent and electrically conductive, like indium tin oxide (ITO). ITO is typically deposited on photovoltaic materials in a solar panel or the liquid crystal display in a smartphone. But indium is expensive and geologically scarce, while manufacturing techniques like vapor deposition, lithography, and etching can be energy-intensive or materially wasteful. There are also growing concerns about indium’s health and environmental impacts.


UW models have shown that electrodes made of earth-abundant materials can be patterned with micron-scale features — smaller than can be seen by the human eye — to make them competitive with ITO electrodes. MacKenzie’s research group can now create this alternative using the advanced capabilities of the JCDREAM-funded printer, as conventional inkjet electronics printers are limited to 20-50 micron features. They will develop copper-based transparent electrodes with nanoscale features that will match or exceed the conductivity and transparency of conventional ITO electrodes. The additive printing process will also eliminate the etching process, reducing negative environmental impacts of the runoff as well as the amount of starting raw material.


The JCDREAM-funded printer

The printer developed at Japan’s AIST and SIJ Technologies. A custom version will be installed at the Testbeds, in order to integrate it with the existing roll-to-roll printer.

Ultimately, MacKenzie’s group aims to create a pathway to sustainable, scalable manufacturing of thin-film solar cells. Currently, indium is a limiting factor for thin-film solar cells due to its cost, toxicity, and long environmental life cycle. The copper-based transparent electrodes could also be used in flat-panel TVs, smartphones, and car windshields. Along with the copper-based alternative to indium electrodes that his group is developing, MacKenzie believes that the revolutionary printing system will enable sustainable solutions for batteries, sensors, fuel cells, and catalysts that rely on lithium, palladium, and cobalt.


“As a cleantech-focused facility that serves academic researchers, startups, and developed companies, the Testbeds are a perfect guidepost for JCDREAM’s mission,” said JCDREAM’s interim executive director David Field. “Our relationship with the Testbeds and other state-supported institutes is crucial to our success. We can’t wait to see the sustainably-sourced and sustainably-produced electronics that Testbeds users will create with this printer.”


JCDREAM is a research collaborative between Washington State University, UW, and the Pacific Northwest National Laboratory, with additional involvement from academic, government, and industrial institutes in the state that are involved in education, research, or manufacturing. It was established in 2015 to stimulate innovation in the use of earth-abundant materials alongside Washington state’s strong clean energy and transportation industries. The upgrade to the Testbeds is just one element of JCDREAM’s program of research, development, deployment, and training, with the goal of national leadership on the challenge posed by unsustainable use of resources and rare earth minerals.

Startup Wins Federal Grant to Develop Battery Materials at Washington Clean Energy Testbeds

Vesicus will use Small Business Technology Transfer funds to develop nanostructured thin films for lithium-ion batteries at Testbeds

Krishna Nadella, Vesicus Co-Founder and CTO

August 3, 2018

Vesicus, an advanced materials startup founded by University of Washington (UW) mechanical engineering alumnus Krishna Nadella (PhD ’09, MS ’02) and UW mechanical engineering professor Vipin Kumar, won $225,000 in Small Business Technology Transfer (STTR) funding to develop nanostructured thin films for lithium-ion batteries at the Washington Clean Energy Testbeds. The STTR program provides federal funding to cooperative research and development (R&D) initiatives between small businesses and research institutions. The UW Clean Energy Institute’s Washington Clean Energy Testbeds is an open-access facility for scaling next-generation clean energy devices and systems. Users from industry and academia can fabricate prototypes, test devices and modules, and integrate systems at the facility.


“The Testbeds enabled Vesicus to win this STTR award because they are specifically designed and equipped to support startup companies that need access to processing and characterization instruments,” said Nadella. “Often, companies like ours cannot afford this equipment unless they raise a lot of equity financing early on, typically before there is proof of product-market fit. More than just an office and lab space, the availability of both technical and business experts make the Testbeds a very effective place to build a clean energy startup.”

Vipin Kumar, Vesicus Co-Founder and CEO and UW Professor of Mechanical Engineering


Vesicus develops and commercializes novel cellular materials made up of cells ranging from tens of micrometers down to single-digit nanometers in size. Its STTR-funded R&D will center on a nanoporous polymer thin film with an initial application as an ion-exchange membrane in lithium-ion (Li-ion) batteries. The nanoporous polyetherimide (PEI) film will have a higher porosity and thermal stability than the separators used in existing models. Compared to the current multi-step process for fabricating battery separators, Vesicus’ continuous process will also result in higher productivity, thereby increasing American global competitiveness in battery manufacturing. Vesicus is using the Testbeds’ roll-to-roll printer and characterization tools for this work.



Scanning electron microscope (SEM) image of Vesicus’ nanoporous polyetherimide (PEI)

Krishna Nadella has been a serial entrepreneur in commercialization of advanced materials for the last 16 years. After the “dramatic failure” of his first startup venture, Nadella returned to UW to partner with his Ph.D. advisor, Kumar. The pair decided to start a new company to commercialize advanced materials and other technologies developed in Kumar’s lab.


Nadella explained, “Our mission at Vesicus is to conduct the R&D needed to develop these novel cellular materials into many applications, each of which may need a specific business model suitable for the particular industry — in some cases it may be licensing, in other cases it may be manufacturing spinoffs, or in yet others it may be joint ventures.”


J. Devin MacKenzie, Washington Clean Energy Testbeds Technical Director and Washington Research Foundation Professor of Clean Energy, Materials Science and Engineering, and Mechanical Engineering at UW

Testbeds Technical Director J. Devin MacKenzie was instrumental in their venture into the Li-ion battery industry. “Devin taught us the various issues faced by the industry and was part of multiple brainstorming sessions centered on potential solutions to these issues using our materials technology and knowledge,” said Nadella. MacKenzie, a Washington Research Foundation professor of clean energy and associate professor of materials science and engineering and mechanical engineering at UW, has over 17 years of experience as a cleantech entrepreneur. His research group will play a key role in characterizing and measuring the performance of Vesicus’ novel materials.


“This type of collaboration is exactly what we envision for the Testbeds,” said MacKenzie. “Vesicus is bringing a key research innovation to market, which is imperative for a clean energy future. We’re excited to support startups like Vesicus with access to top-end instrumentation like our roll-to-roll printer, as well as advising services from technical and industry experts.”


Vesicus aims to develop a scalable design for testing by the end of the summer. Along with Li-ion batteries, other applications of these tunable cellular films include substrates for flexible electronic circuits, separators for the oil and gas industries, and filter membranes for biological technology. Upon successful completion of STTR Phase I R&D, Vesicus will become eligible for Phase II funding.

Three Clean Energy Postdoctoral Fellows Awarded Mistletoe Research Fellowships

UW Chemistry’s Max Friedfeld, Daniel Kroupa, and Jian Wang will each receive $10k in Unfettered Research Grants


July 18, 2018


Washington Research Foundation Postdoctoral Fellow Max Friedfeld and Washington Research Foundation Innovation Postdoctoral Fellows in Clean Energy Daniel Kroupa and Jian Wang have been awarded Mistletoe Research Fellowships for the 2018-19 academic year. The Mistletoe Foundation builds bridges between the academic, entrepreneurial, and civil communities to create a more human-centered and sustainable future through technology. As part of the fellowship, awardees receive a $10,000 Unfettered Research Grant that can be applied to almost any university-approved research-related activity.


Friedfeld, a member of chemistry professor Brandi Cossairt’s group, researches the growth of quantum dots (QDs), which are semiconducting nanocrystals with a wide range of optoelectronic properties and high-tech applications. One such application is next-generation TV and display devices: QD displays can achieve up to a 30% increase in the spectrum of available colors while using 30 to 50% less power than LCD TVs. However, today’s commercial products often rely on cadmium-containing materials that are relatively toxic, so Friedfeld has explored QDs made of an alternate material: indium phosphide (InP). He is developing a new flow-based synthesis method for InP QDs that will grant access to greater control over the reaction, allowing for uniform QD growth and modification of InP QDs while taking less time, resulting in higher yields, and generating less waste than batch InP QD synthesis. To develop the technique, Friedfeld will utilize the Vapourtec V-3 pump flow reactor at the Washington Clean Energy Testbeds. Because the Testbeds already own this crucial piece of equipment, Friedfeld can use the Mistletoe funds to purchase auxiliary equipment and material supplies for his research. He ultimately wants to commercialize this technique, with the aim of improving upon today’s industrial-scale manufacturing of QDs for displays and other applications.


As a member of both Professor Cossairt and chemistry professor Daniel Gamelin’s research groups, Kroupa researches metal-halide perovskites, which have received considerable attention for next-generation solar cells due to low material and manufacturing costs and comparable performance to traditional silicon cells. Kroupa has found that selectively adding ytterbium ions (Yb) to cesium lead halide perovskites (CsPbX3) results in a unique phenomenon known as quantum cutting. Quantum cutting occurs when a single high-energy photon is converted into multiple lower-energy photons by a semiconducting material, due to quantum effects. Using the facilities at the Washington Clean Energy Testbeds, Kroupa’s goal is to harness this property by coating conventional silicon solar cells with a layer of quantum-cutting perovskite. In conventional solar cells, a single photon can only excite a single electron. However, by converting extra energy from high-energy photons into additional low-energy photons that excite additional electrons, Kroupa’s perovskite layer could create a dramatic increase in efficiency at low cost.


Wang’s research in CEI Chief Scientist and chemistry professor David Ginger’s group focuses on an existential challenge for organic photovoltaics: converting heat losses into usable voltage. Organic photovoltaics are a low-cost and flexible alternative to other photovoltaic technologies. However, current device configurations are susceptible to large voltage losses in the form of non-radiative recombination, which occurs when the energy from a photoexcited electron is lost into the surrounding atoms as vibration. These losses often occur due to the use of fullerenes — large, geometric carbon molecules similar to graphene and carbon nanotubes — as the material that accepts excited electrons, so Wang is developing an understanding of non-fullerene acceptors. A guideline to avoiding non-radiative recombination would be invaluable for chemists trying to synthesize new materials for advanced organic photovoltaics. By integrating non-fullerene acceptors, Wang hopes to push forward the commercialization of organic photovoltaics.


In a letter to awardees, Mistletoe wrote, “It is our belief that unfettered research—without pre-negotiated deliverables—is necessary to produce the kinds of scientific and technological advances with the potential to change the world.”


Congratulations, Max, Dan, and Jian!

UW professor and Clean Energy Institute director Daniel Schwartz wins highest U.S. award for STEM mentors

Daniel Schwartz, a University of Washington professor of chemical engineering and director of the Clean Energy Institute. University of Washington

Daniel Schwartz, a University of Washington professor of chemical engineering and director of the Clean Energy Institute, received the Presidential Award for Excellence in Science, Mathematics and Engineering Mentoring (PAESMEM) from the White House Office of Science and Technology Policy and the National Science Foundation this week. The OSTP and NSF recognized Schwartz for his commitment to interdisciplinary graduate education — helping students apply their research to societal and market needs — along with his dedication to recruiting and supporting Native American STEM (science, technology, engineering and mathematics) scholars at the UW.

“I’m proud to join this cadre of dedicated educators and mentors helping students become leading scientists and engineers,” said Schwartz. “Focusing on clean energy science, engineering and resource management at UW has brought top students from across the country to Seattle, where they have partnered with Northwest tribes and businesses to ensure the future of energy is being created here.”

Starting in 2007, Schwartz launched an NSF-funded interdisciplinary graduate training program that used tribal clean energy research partnerships to attract top Native American students to graduate degree programs in UW’s College of the Environment and College of Engineering. The program was continued and expanded in partnership with Washington State University and Salish Kootenai College with U.S. Department of Agriculture funding, eventually including an undergraduate summer research experience program. Since the program launched, 26 students have completed doctoral degrees, with four awarded to Native Americans and four to other underrepresented minorities. Six masters have also been awarded — including two to Native Americans — and a tribal student-led startup company was founded. A signature achievement was the 2016 Alaska Airlines flight from Seattle to Washington, D.C. on fuel partially made from tribal forest thinnings.

“When you take into consideration the low number of Native Americans succeeding in graduate school STEM programs, you must recognize the number of tribal scholars that Dan has helped succeed, in one way or another,” said UW doctoral student Laurel James. “I, for one, would not be where I am today without his mentorship and opportunities for employment as I worked my way through the majority of my Ph.D. as a single parent.”

In addition to his role as an educator and mentor, Schwartz is the founding director of the UW’s Clean Energy Institute, an interdisciplinary research unit that supports the advancement of next-generation solar energy and battery materials and devices, as well as their integration with systems and the grid. With funds from the state of Washington, CEI has supported 152 graduate fellows pursuing clean energy research at UW. Through CEI, fellows receive professional development training, network with industry professionals and top clean energy researchers from around the world, and lead K-12 STEM outreach programs for Washington state schools.

While in Washington, D.C to receive the PAESMEM this week, Schwartz and other award recipients participated in the White House State-Federal STEM Summit to identify educational priorities for the nation.

To read the article on UWNEWS, click here.

WA Flexible Electronics Company and UW Team Win Federal Grant for Manufacturing

Roll-to-roll printing of high-density silver traces on a flexible substrate at the Testbeds. Image credit: Felippe Pavinatto

MicroConnex is partnering with UW professor J. Devin MacKenzie to develop a new manufacturing process for printed flexible electronics at the Washington Clean Energy Testbeds

June 28, 2018

J. Devin MacKenzie, technical director of the Washington Clean Energy Testbeds and Washington Research Foundation professor of clean energy, materials science and engineering, and mechanical engineering at UW, and MicroConnex, Inc., a Snoqualmie, Washington company that performs custom and low-volume flexible hybrid electronics (FHE) manufacturing for high-tech industries, have been awarded a $980,000 grant to solve a key need within the FHE technology base. Using the roll-to-roll printing capabilities of the Washington Clean Energy Testbeds, an open-access lab for fabricating and testing clean technologies, MicroConnex is developing the ability to fabricate novel copper-clad, high-density interconnects on flexible substrates at an industrially-relevant scale.


The research partnership is funded by NextFlex, a Department of Defense-backed consortium of academic institutions and industry partners focused on developing and manufacturing FHE in the United States. UW became one of 30 founding members of NextFlex in 2016.


“This collaboration leverages the Testbeds’ strengths in print-based roll-to-roll electronics and MicroConnex’s expertise in flex circuits and electroplating technology,” said MacKenzie. “We’re excited to create a lower-cost, greener alternative for flexible electronics in medical, defense, aviation, and consumer products.”


J. Devin MacKenzie, Washington Clean Energy Testbeds Technical Director and Washington Research Foundation Professor of Clean Energy, Materials Science and Engineering, and Mechanical Engineering at UW

Flexible hybrid electronics represent a new class of electronics that are bendable, stretchable and highly robust — well matched to applications such as wearable electronics, on-body sensors, and electronics for extreme environments. Furthermore, FHE are both thin and lightweight ­— the total thickness of FHE circuitry can approach 25 micrometers, and replacing rigid electronics with FHE can result in a weight reduction of over 50%. The ability to manufacture FHE at scale using advanced printing techniques could revolutionize devices like compact wireless transmitters, actuators, and medical sensors. In addition, FHE technology could be the cornerstone of a new era of “smart” and conformable consumer products to better interface with the human body, further advancing the efficiency and interconnectedness of our world.


“We are operating at the cutting edge of flex manufacturing, where high-risk, high-reward R&D is needed to deliver cost-competitive, high-tech solutions,” said Steve Leith, vice president of engineering and technology at MicroConnex and UW chemical engineering alum (B.S. 1991; Ph.D. 1998). “As a small company, MicroConnex would be challenged to manage the financial and technical risk of a project of this scope without the Testbed facilities and UW as a partner. The Testbeds’ state-of-the-art equipment, staff expertise, and IP terms are ideal for this research partnership and our business needs.”


MicroConnex’s new FHE manufacturing process is fully additive and eliminates many of the byproduct waste streams that result from conventional subtractive manufacturing techniques such as etching. Using the new process, a flexible substrate is first printed with a “seed” circuit pattern less than 300 nanometers thick, before the interconnects are built up along the pattern using electrodeposition. The project represents a significant advance for FHE manufacturing, moving away from typical subtractive circuitry fabrication processes while directly addressing fundamental challenges of circuit density, substrate flexibility, and manufacturing cost.

Close-up of the photopolymer plate (printing master) used for flexographic printing.
Image credit: Felippe Pavinatto

Ultra-high resolution silver conducting traces printed via flexography. Image credit: Felippe Pavinatto


MacKenzie is an expert in printable and flexible electronic materials, having spent over 17 years in the field as a scientist, research leader, and seed-stage entrepreneur. His research team and MicroConnex have already begun their work on the NextFlex grant, with initial focus on demonstrating the ability to print high-resolution silver nanoparticle seed films on flexible polyimide substrates.  Subsequent research phases will develop the electrodeposition processes necessary to transform the seed film into a working circuit.  At the conclusion of the project, MicroConnex and the Testbeds will provide direct access to the developed technology to NextFlex members for both R&D and commercialization purposes.

Clean Energy Solutions for Public Health in Puerto Rico

Electrical engineering Ph.D. student Mareldi Ahumada installs solar panels with a Jayuya community member. Photo: Dennis Wise / University of Washington

May 18, 2018

Chemical engineering professor Lilo Pozzo and a group of CEI researchers and public health scientists traveled to Jayuya, Puerto Rico this spring. The team visited homes and community centers, interviewing dozens of caregivers and residents who use electronic medical devices, as part of a long-term field study on the impact of power loss on public health. They also donated and installed 17 solar-battery nanogrid systems — prototypes of a sustainable, clean energy infrastructure that can buoy public health in rural areas when power grids fail (in addition to the four systems they installed on a November trip). Pozzo and her team hope to return later this summer.

Read the full UW story about their work here.

Pushing Magnetic Materials to the Atomically-Thin Limit

Researchers sandwiched two atomic layers of CrI3 between graphene contacts and measured the electron flow through the CrI3. Photo: Tiancheng Song

May 3, 2018

Magnetic materials are the backbone of modern digital information technologies, such as hard-disk storage. A UW-led team has now taken this one step further by encoding information using magnets that are just a few layers of atoms in thickness. This breakthrough may revolutionize both cloud computing technologies and consumer electronics by enabling data storage at a greater density and improved energy efficiency. In a study published in Science, the researchers report that they used stacks of ultrathin materials to exert unprecedented control over the flow of electrons based on the direction of their spins — where the electron “spins” are analogous to tiny, subatomic magnets. The team used instruments in CEI’s Research Training Testbed for this research. Read the full story featuring physics grad student Tiancheng Song and physics postdoc Xinghan Cai from CEI member faculty Xiaodong Xu’s lab here.

Inspiring Future Engineers

Gabriella Tosado building solar cars with middle school students. Photo: Tara Brown / University of Washington

Read the original story here.

Chelsea Yates
January 9, 2018

“I’m from Miami, Florida, where climate change isn’t just real; it’s personal,” says chemical engineering graduate student Gabriella Tosado. “My home city is seriously threatened by rising sea levels, and not only do I want to do my part to develop solutions to help fight climate change, I want to encourage young people — our next generation of engineers and scientists — to do the same.”

The first scientist in her family, Tosado triple-majored in chemistry, environmental science and policy, and religious studies at the University of Miami before switching gears to pursue a dual Ph.D. in chemical engineering and nanotechnology and molecular engineering. At the UW, she has melded her interests in sustainable engineering and community involvement through the UW Clean Energy Institute (CEI), where she’s been coordinating K-12 outreach programs since 2016.

We recently caught up with Tosado, who was named to the Husky 100 last spring, to learn more about her research and passion for inspiring underrepresented students — particularly young women and students of color — to pursue STEM disciplines and careers.

Why did you decide to study chemical engineering at the UW?

Although I love chemistry, I wanted to pursue a solutions-focused, application-oriented course of study for my graduate work, so I started looking at engineering programs.

When I visited Seattle to check out UW’s chemical engineering program, I discovered CEI, which had just opened on campus, and is working to advance clean energy technologies through solar energy, battery and grid research. When I realized I could get in on the ground floor of CEI’s innovative research, I decided that UW was the place for me.

Gaby Tosado in the lab

In her research, Tosado explores how to develop and stabilize perovskite solar cells.

Tell us about your research interests.

I’m working in ChemE professor Qiuming Yu’s lab to develop and stabilize perovskite solar cells. Perovskite is an exciting material that’s pretty new to the solar world. Its unique crystal makeup gives it a lot of interesting properties, and it can be printed on flexible materials, which is really cool. There’s hope that it may soon become a cheap, efficient, and high performing alternative to conventional — and expensive — silicon solar cells. But in its current state, it’s too unstable. We want to come up with a way to stabilize it so that it can be commercialized, ultimately making solar energy more accessible and affordable.

You are CEI’s first education fellow and outreach coordinator. What does that involve?

I develop outreach activities for CEI through the CEI Ambassador Program. This includes everything from creating curriculum materials and organizing tours to traveling across Washington state to teach K-12 students about clean energy and encourage them to think about going to college to study STEM. I’m proud to say that we’ve reached more than 40,000 students across the state to date.

Through CEI, I also started working with Pacific Science Center, and this year, I’m serving as a Pacific Science Center Communications Fellow. A few times each quarter, you can find me leading workshops and demonstrations at the Center as part of one of their many public programs, such as Meet a Scientist Day and Paws on Science Research Weekend.

Grabby teaching in an elementary class

Through CEI’s outreach ambassador program, Tosado travels across Washington state teaching students about clean energy and sustainable engineering. So far, the program has reached more than 40,000 students across the state. Photo: Tara Brown / University of Washington

You are a founding member of Women in Chemical Engineering (WChE). Why did this group get started?

ChemE assistant professor Elizabeth Nance started this group in 2016 to empower, educate and advocate for women in chemical engineering at all levels — undergraduates, graduate students, faculty and alums. In a male-dominated field like chemical engineering, I think it’s easy for women to feel invisible. With WChE we wanted to create a welcoming and open space for dialogue, mentorship and collaboration. We host professional development events, industry panels, and as the outreach coordinator, I create community networking and educational outreach opportunities. And we’re always excited to welcome new members! All students, regardless of gender, are encouraged to join and help us advocate for women in our discipline.

This fall, you organized “Introduce a Girl to Nano,” a nanotechnology fair to encourage young girls and women toward STEM fields. Tell us about it.

I organized “Introduce a Girl to Nano” on behalf of CEI and WChE and with help from some fantastic fellow UW students. In celebration of National Nanotechnology Day, our fair featured a variety of hands-on experiments for girls to try. They could react gold nanoparticles, race solar cars, create graphene circuits and rainbow thin film, and so much more! We offered STEM patches to Girl Scouts who participated, which was great fun.

This event was actually a follow-up to “Introduce a Girl to Photonics,” a fair I organized for CEI in 2016. That year 50 girls participated; this fall’s event brought in 277. I’m looking forward to seeing that number grow even more next year, though we haven’t decided on the theme yet. We’re considering robotics, coding and polymers, as well as a few others…

A lot of your outreach focuses on introducing underrepresented communities to science and engineering. In your opinion, why is it important to bring more diversity to STEM fields?

I think it’s important for girls and students of color to see women and people of color pursuing STEM disciplines in college. When I was a kid, no one in my immediate family had a background in science, and I didn’t really have any women mentors in science to look up to. So I carved out my own path. I often think about how meaningful it would have been to have someone to look to and say, “She did this; I can do this, too.” I’m now in a position where I can be that person for someone else, and that’s really motivating.

Speaking more broadly, engineers and scientists need to come up with solutions to today’s challenges, but to do so effectively, we need to be more creative and diverse in our problem-solving and ways of thinking. We need dynamic solutions in STEM, and the only way to get them is to diversify the field. The more difference, the more opportunity to cultivate and implement new ideas and approaches.

Students with electronics

“I often think about how meaningful it would have been to have someone to look to and say, ‘She did this; I can do this, too.’ I’m now in a position where I can be that person for someone else, and that’s really motivating,” says Tosado. Photo: Tara Brown / University of Washington

Why do you make time for outreach?

Outreach keeps me sane! In graduate school, there are many failures. You design, you test, and more often than not, you fail. So you start again. There’s a lot of stress.

But in outreach there’s so much wonder and excitement; it’s infectious and promising! The smiles on kids’ faces when they test out solar spinners they’ve just made, or when they realize they can make a battery from scratch — those moments are awesome. And I can’t tell you how much it brightens my day to see a bunch of little girls line up to race solar cars. That’s the best!

Designing and Growing Quantum Materials for Energy and Information Technology

UW physics professor Jiun-Haw Chu takes a holistic approach to the development and characterization of materials with new or unusual electronic and magnetic properties

March 22, 2018

Jiun-Haw Chu, Washington Research Foundation Innovation Assistant Professor of Clean Energy & Physics, was recently awarded $1.2 million from the Gordon and Betty Moore Foundation’s Emergent Phenomena in Quantum Systems (EPiQS) initiative in support of the discovery and investigations of atomically thin and layered quantum materials. He has also been named a 2018 Alfred P. Sloan Foundation Research Fellow, having been nominated by his peers in recognition of outstanding performance and potential within the field of quantum materials. CEI talked with Chu about how these prestigious awards will advance his research, his career path, and his experience at UW thus far.

Tell us about your research. How do you design and grow these materials from the bottom up?

My group is focused on the design, growth, and characterization of novel quantum materials. Quantum materials have electronic, magnetic, and optical properties that could revolutionize energy and information-processing technologies. We can grow crystals from 85% of the elements on the periodic table through use of the flux method, in which the components are dissolved, combined, then slowly cooled. This process results in large single crystals in a relatively short time scale, ideal for exploring a wide range of material phases. Our approach differs from those that are solely focused on measurements or material synthesis, because we combine intuition from physics, chemistry and materials science. We look at the chemical formula of a material and see what atoms can be replaced to create an exciting new property.

Quartz glassware from Chu’s lab, specially-made for crystal growth

Why did you choose the field of quantum materials?

Quantum materials is a field that allows me to touch upon some of the most profound concepts in physics, such as topology and quantum field theory. At the same time, it also requires hands-on experiments with materials that could actually impact society. I like to travel back and forth between abstract ideas and down-to-earth experiences.

What are some of the possible applications for the quantum materials that you are researching?

While our group is generally focused on fundamental studies and discovering the properties of new quantum materials, some significant research targets include high-temperature superconductors and topological insulators. Harnessing the unique magnetic and electrical properties of superconductors at accessible temperatures would be ideal for grid-scale power transmission, battery-powered airplanes, and advanced MRI machines. Topological insulators, which are materials that conduct electrons at the surface but act as insulators within the bulk, show promise in quantum computing applications. 

Congratulations on the Moore Foundation grant! What advances will this allow you to make?

The Moore Foundation has supported many of the prominent figures in the field of quantum materials, so I feel privileged to be a part of that community. The proposed focus of the EPiQS research is to be able to grow a wide variety of heterostructures – crystals with regions or layers of multiple different materials. The interfaces between layers, called heterojunctions, are often the site of new material behaviors or properties.

You have also been recognized by the Sloan Foundation for your contributions early on in your career. What advice might you give a graduate student or postdoc that is looking to make an impact early on in their own clean energy research?

It’s very hard to predict what will be the next big thing in 5-10 years. To be honest, I was very lucky, and happened to be at the right place at the right time. Work on something you are passionate about, something you love, and you won’t regret it.

Tell us about your relationship with UW’s Clean Energy Institute.

CEI Director Dan Schwartz played a big part in my decision to become a professor at UW. Over lunch, Dan illustrated how CEI could be a platform for interdisciplinary, collaborative research with a focus on materials and technology that could impact society. Shortly after I arrived on campus, CEI helped me quickly establish my group and connect to other researchers. I collaborate with many other CEI professors, like my fellow physicists Xiaodong Xu, David Cobden, and Kai-Mei Fu, and am looking forward to doing even more work together through the Molecular Engineering Materials Center (MEM-C). These collaborations will also help my research under the Moore grant, as these professors have expertise in the physics of nanoscale and 2D materials.

CEI has also facilitated our efforts to build a team with the Pacific Northwest National Laboratory (PNNL) to create new heterostructures. CEI has funded two of my graduate students — Shua Sanchez and Josh Mutch — as part of the Graduate Fellowship Program, which has been a great way for them to connect to other researchers on campus and the broader cleantech community. Finally, I have collaborated with CEI chief scientist and chemistry professor David Ginger and Professor Xu to support research on the behavior of charge carriers in single-crystal perovskites, thanks to a CEI Exploration Grant.

CEI Graduate Fellow Shua Sanchez, performing a glassware modification

You’re coming up on two years at UW! What have you enjoyed the most about your time here?

Everything! My wife and I were already in love with Seattle when we were graduate students, long before we moved here. I also truly enjoy the friendly and supportive environment at UW, and enjoy interacting with my colleagues, and brilliant and hard-working students.

CEI Research Highlights: January 2018

January 24, 2018

Scalable Planning for Energy Storage in Energy and Reserve Markets

As renewable resources are integrated into the grid, energy storage must be planned and deployed in order to harness and balance the natural fluctuations in electricity generation. Electrical engineering professor Daniel Kirschen and his students have continued to develop a model for optimal siting and sizing of storage utilities by adding a profit constraint for proposed systems. The Kirschen group utilized the Western Electricity Coordinating Council (WECC) testbed for their simulations. The 240-bus (power transmission node) system represents the Western Interconnection grid that spans from the Pacific past the Rockies and includes British Columbia, Alberta, and part of Baja California. The results of the case study, as published in IEEE Transactions on Power Systems, show that increased rate-of-return requirements result in decreased deployment of energy storage. A comparison between lithium-ion batteries and above-ground advanced adiabatic compressed air energy storage (AA-CAES) shows that AA-CAES has the higher potential for reducing system-wide costs. However, AA-CAES technology is still at the pilot stage, with the first-ever utility-scale installation scheduled to open in Germany later in 2018. Lithium-ion storage systems are not deployed in any of the model market scenarios at current investment costs, but those costs are expected to continue to decrease for the next 10 years. At a 30% decrease in investment cost, lithium-ion installations are projected to be profitable investments within the Western Interconnection energy market.

Self-Cleaning Surfaces for Solar Panels

Solar photovoltaic cells can experience drops in power generation efficiency when dust accumulates on the cover glass. In lieu of regular manual cleaning, engineers have modeled self-cleaning technology after the leaves of the lotus plant, using a microstructured surface to bead up water droplets that collect environmental contaminants as they roll off. However, this movement is random, so these technologies cannot clean the whole surface without an additional tilting mechanism. CEI Graduate Fellow Di Sun, advised by electrical engineering professor and Institute for Nano-engineered Systems (NanoES) director Karl Böhringer, has created a prototype that methodically cleans an entire surface using a new technology called Anisotropic Ratchet Conveyors (ARCs). As presented this June at the 19th International Conference on Solid-State Sensors, Actuators and Microsystems, in Kaohsiung, Taiwan, a self-assembled monolayer is deposited onto a silicon surface and etched into a rung pattern, which induces the water droplet to travel on a predetermined path when vibrated. The droplets can even be made to move uphill, up to a 15° incline. The ARC layer is optically flat and transparent, resulting in less than 1% degradation of light relative to bare glass. This November, Sun shared an update to his research at the International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, in Kanazawa, Japan. The self-cleaning technology has successfully been applied to a photovoltaic module, and the ARCs can now be fabricated using a polymer-based stencil instead of the etching technique, helping to maintain the hydrophobicity of the underlying surface. Sun’s work has recently received support from the Amazon Catalyst program, a collaboration between Amazon and UW’s CoMotion to help fund “bold, globally-impactful, disruptive projects.”

Estimating Chemical Potential in Oxide-Supported Metal Nanoparticles

Metal nanoparticles (NPs) supported on oxide surfaces are often used in industrial catalysis for energy and environmental technologies, such as in the production of clean fuels and the cleanup of exhaust emissions. The catalytic activity and deactivation rates of metal atoms within NPs have been shown to depend upon NP size and the properties of the supporting oxide, but catalysis chemists have yet to be able to quantitatively predict these effects. In this paper, published in ACS Catalysis, Professor Charles T. Campbell (chemistry) and graduate student Zhongtian Mao present a method of estimating the chemical potential of these metal atoms. This represents a significant step toward predictions of catalytic activity and deactivation rates, as those characteristics are correlated with chemical potential in known ways. For late transition metals, the chemical potential of the atoms in a particle of a chosen size can be modeled as a function of the surface energy of the metal, the adhesion energy at the NP/oxide interface, and the molar volume of the metal. Campbell also presents a linear estimation of that adhesion energy, based on oxygen density on the surface of the oxide and known thermodynamic properties of the metal and the oxide. The model is the first to allow for predictions of chemical potential vs. NP size for different metals on different oxides, with relative errors better than ~20%.

Helical Luminescence in a Two-Dimensional Magnet

This June, a team led by Professor Xiaodong Xu (physics; materials science & engineering) discovered the first two-dimensional (2D) material with intrinsic magnetism: chromium triiodide (CrI3). This December, Xu, physics professor David Cobden, CEI Graduate Fellow Kyle Seyler, and graduate students Ding Zhong and Bevin Huang observed photoluminescence in monolayer CrI3 crystals, as detailed in a paper published in Nature Physics. This observation is a first for a magnetic monolayer, and curiously, the photoluminescence exhibits spontaneous circular polarization. The emitted light waves trace out a helix, where the clockwise or counterclockwise orientation is determined by the magnetization direction of CrI3. This circularly polarized photoluminescence does not require an external magnetic field, in contrast to similar phenomena in other materials. The UW team also studied bilayer CrI3, which did not exhibit circular polarization in its photoluminescence. This observation supports their previous finding: that CrI3 bilayers have zero net magnetization. These discoveries are promising for further magneto-optical studies, as well as novel magneto-optoelectronic devices and van der Waals heterostructures. Described as “atomic Lego,” these devices consist of artificially stacked monolayers held together by van der Waals intermolecular forces. Van der Waals heterostructures already show promise in next-generation solar cells, LEDs, and transistors, and the UW team’s investigations of CrI3 could expand these applications to include energy-efficient magnetic information processing and storage.


A New Battery for Grid-Scale Energy Storage

Shanyu Wang (left) and Mengyu Yan (right), pictured with the x-ray diffractometer (XRD) located at CEI’s Washington Clean Energy Testbeds. Photo: Owen Freed / University of Washington

UW materials scientists make breakthrough in study of alternative to lithium-ion

January 23, 2018

The lithium-ion batteries found in smartphones, power tools, and electric cars are small and lightweight, but the technology is generally considered to be infeasible for energy storage at a much larger scale. The typical cathode material (lithium cobalt oxide) is expensive and susceptible to overheating, and the electrolyte (dimethyl carbonate) is highly flammable. If these batteries are overcharged or are physically damaged, there can be explosive consequences. To circumvent these issues and develop batteries that can store energy at the utility scale, battery researchers have been focusing on models that use earth-abundant elements and water-based electrolytes.

University of Washington materials science & engineering (MSE) researchers have made a breakthrough in understanding the mechanics of a zinc-ion, aqueous-electrolyte model. This alternative technology is lower in energy density than lithium-ion batteries, with 30 times the power density. Jihui Yang, the Kyocera associate professor of MSE and MSE department chair, said that the research “points to a high-performance, low-cost, safe, and environmentally-friendly battery, ideal for grid energy storage.”

Mengyu Yan, a Washington Research Foundation (WRF) Innovation Postdoctoral Fellow and the lead author of the study published in Advanced Materials, and Shanyu Wang, also a postdoctoral researcher in Yang’s group, created the cathode by growing vanadium pentoxide (V2O5) nanowires on graphene.

Scanning-mode electron microscope image of bare graphene sheets (a) and as-prepared V2O5 nanowires, after liquid-phase deposition onto the graphene (b)


The resulting vanadium oxide-graphene (VOG) material was found to contain water molecules within the layers of the structure, like the frosting of a layer cake.

Artist’s representation depicting structural water molecules within crystalline V2O5 layers

The existence of these water molecules is key to optimizing the mechanism of charge and discharge.

During charge and discharge, zinc ions intercalate between the VOG cathode layers. Intercalation – reversible insertion and de-insertion, through chemical processes – is a vital design element of the majority of rechargeable battery technologies, including the lithium-ion model. The major finding of the UW researchers was a curious “lubricating” phenomenon that takes place during intercalation. The aforementioned water molecules found within the VOG increase interlayer distance, and also form weakly-bonded “shields” around the zinc ions, reducing their effective charges and thus their attraction to oxygen atoms within VOG crystals.

Artist’s representation depicting interlayer gap and shielding effects of water molecules during Zn intercalation

When the structural water molecules were removed by annealing VOG at 350°C, both peak performance and performance over multiple cycles dropped significantly. High rates of intercalation result in faster power transfer and longer battery lifetimes, which are primary concerns of grid-scale battery engineers.

The research benefited from a partnership with the Pacific Northwest National Laboratory (PNNL), located in Richland, WA. PNNL is a leading member of Battery500, a U.S. Department of Energy (DOE) program that involves multiple national labs and research universities, which lead author Yan said was vital to the project:

“Battery500 members shared important information about the latest battery technologies and their potential uses. In this case, zinc-based models were promising for grid-scale use. As well, we were able to rely on the advanced NMR [nuclear magnetic resonance] instrumentation and expert technicians at PNNL to help us collect and interpret data.”

Both Yan and Wang feel optimistic about the future of the technology, but highlighted different areas for advancement. Wang shared his views on the developments needed to get a zinc-ion battery on the market:

“We now understand the physics of this model, so we’re excited about applying our understanding of water’s role in intercalation to other types of battery technologies. While vanadium is cheap, it’s relatively toxic, so we will try different materials like manganese oxide. We could also try different polar solvents instead of water, to try and further improve efficiency. Graphene is a great material for studying [the intercalation mechanism], but it makes this particular prototype too expensive for a grid scale, so we need to explore a different material.”

Yan was excited about the potential for “further cooperation with PNNL to reduce the price, such that this technology could be implemented for grid-scale energy storage.”

Along with the NMR data collected at PNNL, the researchers utilized CEI’s Washington Clean Energy Testbeds to perform x-ray diffraction (XRD), cyclic voltammetry (CV), and scanning-mode electron microscopy (SEM). The characterization-focused facility allowed Yan and Wang to collect information about the crystal structure and electrochemical properties of their device.

Yan earned his Ph.D. in materials science and technology at Wuhan University of Technology (Wuhan, China), where he was supervised by Liqiang Mai, the chair professor of materials science. Their relationship has continued to be fruitful, as Mai and his research group contributed to discussions of the particulars of the intercalation model, analysis of electrochemical data (cyclic voltammetry, energy density, and power density), and authorship of the Advanced Materials paper.

Co-authors of the paper include Dr. Ying Chen, Dr. Yuyan Shao, Dr. Karl. T. Mueller, and Dr. Jun Liu at Pacific Northwest National Laboratory; Pan He, Dr. Qiulong Wei, Kangning Zhao, Dr. Xu Xu, Prof. Qinyou An, Yi Shuang, and Prof. Liqiang Mai of Wuhan University of Technology.

For more information, contact Dr. Yan at myyan@uw.edu and Professor Yang at jihuiy@uw.edu.

UW, Tsinghua Researchers Explore Challenges and Opportunities for Smart, Renewable Energy Grids

UW professors Zhang (second from left) and Kirschen (third from right), with Tsinghua University professors Zhang (far left), Kang (third from left), Chen (second from right), and Zhu (far right). Photo: Owen Freed / University of Washington

January 2, 2018

University of Washington electrical engineering professors and CEI member faculty Daniel Kirschen and Baosen Zhang hosted faculty from Tsinghua University (Beijing, China) for a symposium on smart energy systems on December 8, 2017. The Tsinghua group was led by Chongqing Kang, professor of electrical engineering and Chairman of the Executive Committee of the Department.

Brian Johnson presenting on novel modeling techniques for networks within low-inertia power systems. Photo: Owen Freed / University of Washington

“Our two groups have collaborated for a number of years because we have a common interest in developing tools and techniques that support the operation and development of a sustainable, economic, and reliable supply of electrical energy,” Kirschen said.

At the symposium, Brian Johnson, who will join UW electrical engineering as Washington Research Foundation (WRF) Innovation Assistant Professor of Clean Energy in spring 2018 from the National Renewable Energy Laboratory (NREL), described novel modeling techniques for networks within low-inertia power systems. As large conventional power plants are replaced with small energy generators, the inertia of the system – its ability to handle fluctuation in supply and demand of power – decreases. Each individual generator requires its own DC-to-AC inverter, so the grid becomes exponentially more complex in addition to its increased volatility. Johnson explained that the power and voltage characteristics of inverter-generator systems can be aggregated using his technique, allowing operators to model the grid similarly to present conditions.

Guiping Zhu, associate professor and associate dean of electrical engineering at Tsinghua University, spoke about China’s present challenges in optimizing large-scale battery storage. “Wind power is intermittent, fluctuating, and has strong temporal and spatial correlations,” she noted, so she and her team created a model using real data from 34 Chinese wind farms. By simulating outputs, optimal storage capacity can be calculated, and model costs can be compared. These principles are promising for implementation throughout a renewable grid.

Ning Zhang, associate professor of electrical engineering at Tsinghua University, presented on multiple energy systems, in which energy inputs (coal, gas, hydro, wind, solar) interact to produce utility outputs (electricity, cooling, heating). He explained a complex model in which power converters within “hubs” can be optimized, such that a building, city, or region fulfills its utility demands at the lowest total cost of energy generation.

Qixin Chen, also an associate professor of electrical engineering at Tsinghua University, concluded the symposium with an examination of the economics of storage in Chinese electricity markets. In recent history, China has ramped up investment in battery technology, in order to fully leverage wind and solar sources, as well as power the world’s most rapidly growing electric car market. While initial capital investment is costly, Chen estimates that battery storage could save $300 per kilowatt over traditional “peak-shaving” (power throttling) policies in the long run. Chen’s economic model compares the differences in prices of grid power, power used for frequency regulation, and power reserves when storage is properly implemented to when it is not. The model illustrates that without proper battery storage, traditional thermal plants should remain profitable because they provide reliable power when a largely-renewable grid requires regulation or supplementation. However, if 300 GW of total storage is implemented by 2030, the need for thermal plants will be significantly diminished. Chen concluded, “It is not renewables that will be the death of traditional plants, it is the storage of those renewables.”

In 2015, UW, the State of Washington, Tsinghua University, and Sichuan Province formalized a relationship when the parties signed a “2+2 MOU”  to support collaborative research on clean energy and sustainable cities. As part of this agreement, in September, Tsinghua University’s Energy Internet Research Institute (EIRI) and UW’s Clean Energy Institute signed a collaboration agreement and EIRI pledged two seed fund projects: one on low emission transportation led by civil and environmental engineering professor Yinhai Wang, and the other for research led by professors Jim Pfaendtner (chemical engineering) and Kirschen on multi-scale engineering of clean energy systems.

Helping Puerto Rico & Reusing Bus Batteries: The New York Times on CEI

Left: Lilo Pozzo, The Weyerhaeuser Endowed Associate Professor of Chemical Engineering. Right: CEI Graduate Fellow and Battery Informatics CTO Matt Murbach installing used King County Metro bus batteries at Twin Islands

December 11, 2017: The New York Times features chemical engineering professor Lilo Pozzo, chemical engineering Ph.D. student Matt Murbach, and CEI director Dan Schwartz in an article published this week about clean energy innovation in Washington and California. “Rethinking Electric Power, Prompted by Politics and Disaster” highlights Pozzo’s work in Puerto Rico with a group of students on health-related energy resiliency issues and Murbach’s and Schwartz’s research on diagnosing the state of health in batteries and finding opportunities for reuse. Pozzo is hoping to return to Puerto Rico over spring break with students to continue these efforts. Murbach, the startup he helped found, Battery Informatics, and students are monitoring the installation of the King County Metro bus batteries on Twin Islands—demonstrating how these used batteries have potential for real-world stationary energy storage applications.

“Providing clean energy to the inhabitants of our planet is a major challenge to future generations. The University of Washington is to be congratulated for establishing an Institute where faculty and students can work together to tackle the difficult global challenge of energy sustainability.”
– Mildred Dresselhaus, Professor of Physics and Electrical Engineering, Emerita and Institute Professor, Massachusetts Institute of Technology
“Energy competition is opening up in a variety of ways, the push for carbon control will continue, and the rate of technology advancement is exponential. All the things I’ve seen at the CEI are just perfect for the way we see things going in energy. You guys are at the cutting edge. We’re counting on you.”
– Ronald Litzinger, President, Edison Energy