PNNL

Three early career scientists from PNNL have been awarded funding to conduct innovative battery research supporting the mission of the Department of Energy’s Battery500 Consortium.

Xia Cao, Bingbin Wu, and Lili Shi are among eight recipients of the consortium’s Young Investigator Awards program. PNNL leads the multi-disciplinary consortium with the objective of significantly increasing the amount of energy in lithium-ion batteries that currently power electric cars. The consortium intends to build a lithium-metal battery with a specific energy of 500 watt-hours per kilogram and a cycle life of 1000 cycles.

The investigator awards provide young researchers with six months of research funding, mentorship from leading battery scholars, and project management experience. Funding for the Battery500 Consortium Young Investigator projects comes from DOE’s Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office.

“The three young investigators from PNNL, along with five other young investigators from other institutes, demonstrated great understanding and knowledge of the scientific challenges of the Battery500 Consortium, and proposed credible new approaches to solve these challenges,” said Jun Liu, consortium director and a joint appointee of PNNL and the University of Washington. “We are very excited and are looking forward to incorporating some of these new ideas into our future research activities.”

Xia Cao 

Cao’s project is one of two top-ranked proposals that received $50,000 in funding from the consortium. The postdoctoral researcher is focused on developing new electrolytes to enable high-energy efficiency cycling in lithium sulfur cells. “The target is to find electrolytes that will protect the electrodes, both Li metal and sulfur in the batteries,” said Cao, who describes electrolytes like blood in the human body. Cells cannot function without electrolytes.

Cao, who joined PNNL two years ago, has a list of objectives for her project: to make lithium metal safe to use by leading dendrite-free lithium deposition and eliminating short circuits; and how to better utilize the abundance and low cost of sulfur.

Cao is working under the mentorship of Jason Zhang, a PNNL Laboratory Fellow and a consortium principal investigator.

“Xia is an outstanding scientist who has the great insight on the chemistry and electrochemistry of electrolytes,” Zhang said. “Her work in this project may lead to new breakthroughs on the development of novel electrolytes for energy storage systems.”

Cao grew up in Jinhua, a city in central Zhejiang province in eastern China. She is the only scientist in her family. However, her parents are passionate about herbal medicine, often hiking through the mountains gathering herbs. Cao sees a lot of similarities between herbal medicine and her role in battery research, including diagnosing a problem and developing and formulating a safe, high-performance recipe.

Cao earned her doctorate in physical chemistry from the University of Munster in Germany (a well-regarded institute for battery research), under the supervision of distinguished expert Professor Martin Winter. Cao has been focused on electrolyte research since 2010, when she began her work in batteries.

Outside the lab, Cao enjoys fishing, hiking, and planting.

Bingbin Wu

Wu’s project seeks to identify a liquid coating that can be applied to the metal layer on lithium-metal surfaces to separate the reaction between the metal and the electrolyte. The reversible and thin metal layer is designed to increase the energy barrier of an electrolyte, while also allowing lithium-ion diffusion. The method is expected to prolong the life of the current lithium-metal battery by involving more electrolytes during the life period. Wu received $40,000 in funding for his research.

He is focused on how batteries need to become more safe, reliable, and successful in the market, particularly to benefit electric cars.

“If we’re successful, the industry will change,” Wu said. “People really want more from batteries.”

Wu, a materials scientist, joined PNNL in 2018 as a postdoctoral researcher. He earned his doctorate in physical chemistry from Wuhan University in China. His mentor is Jie Xiao, a group leader in PNNL’s Energy Processes and Materials Division, who has a joint position in the chemistry and biochemistry department at the University of Arkansas.

“Bingbin always comes up with ideas that are not only innovative but relevant and effective in addressing the challenges in realistic battery systems,” Xiao said. “Colleagues like to consult him because of his industry experiences.”

Wu recognizes the unique perspective he brings to battery research, having worked previously in battery manufacturing. He developed a high-density, lithium-metal battery as a senior engineer for Amperex Technology Limited, one of the world’s leading producers of lithium-ion batteries.

When Wu is not conducting research, he enjoys all things related to basketball. He’s a basketball fan with huge admiration for Yao Ming. Every Saturday at noon, Wu takes to the court with other PNNL employees to shoot hoops. He also writes poetry.

Lili Shi

Shi’s project is designed to enable faster evaluations of separator conductivity and selectivity for long-cycle lithium-sulfur batteries. In these batteries, lithium metal is the anode and sulfur is the cathode. Shi considers lithium-sulfur to be the next-generation battery given it is less expensive, abundantly available, and has a higher energy density.

Sulfur becomes polysulfide during the discharge process, which means it can be dissolved in the electrolyte. The separator is important because it can provide strong ionic connectivity and prevents the polysulfide from moving. In Shi’s research, she plans to design a setup that can measure conductivity and selectivity, producing more accurate results.

Like Wu, Shi is working on the project under the guidance of Xiao. She received $40,000 to conduct her research.

“Lili is extremely dedicated to battery research,” Xiao said. “As a young scientist, instead of rushing for publications, Lili prefers to identify the real problems in batteries and solve them, followed by knowledge dissemination.”  

Shi earned a doctorate in applied chemistry from Beijing Institute of Technology and has worked at PNNL for more than two years.

She is a lover of language. Shi is a volunteer at the Chinese language school in Richland, working with children to adults. Shi also enjoys reading classic novels and The Economist.

“English is a very beautiful language,” Shi said.

Project impacts

Wu Xu, a PNNL chief scientist who manages the Battery500 Young Investigator projects, sees great potential for advancing batteries with the eight projects.

“The consortium focuses on the design of novel electrodes and cell architectures, the development of new electrolytes, the protection of lithium-metal anode, and the investigation of electrode/electrolyte interfaces,” said Xu, also a consortium principal investigator. “These are also the topics for the Young Investigator Award winners to work on, but from their own perspectives. We hope at least one of the eight awarded projects could succeed and be applicable in 1–2 ampere-hour pouch cells, then it will help the consortium steadily move forward to reach the goal.”

The other recipients of the Young Investigator Awards are:

• Zulipiya Shadike, the other top-ranked proposal recipient, Brookhaven National Laboratory
• Snehashis Choudhury, SLAC National Accelerator Laboratory/Stanford University
• Tao Deng, University of Maryland
• Yue Gao, Penn State University
• Xiaoyu Jiang, University of Washington