Ph.D., Materials Science & Engineering, 1995, Zhejiang University, China
M.S. Materials Science & Engineering, 1988, Harbin Institute of Technology, China
B.S. Mechanical Engineering, 1982, Jiamusi University, China
- Professor, UMD Director of Center for Research in Extreme Batteries (CREB), University of Maryland, College Park 8/2016 – present
- Associate Professor, University of Maryland, College Park, 8/2012 – 7/2016
- Assistant Professor, University of Maryland, College Park, 8/2007 – 7/2012
- Assistant Professor, Tennessee Technological University, 8/2003-7/2007
- Research Scientist, Texas A&M University, College Station, 3/1999-7/2003
- Assistant Research Scientist, Texas A&M University, College Station, 7/1998-2/1999
- Associate Professor, Zhejiang University, China, 7/1997 – 6/1998
- Postdoctoral Research Associate, Zhejiang University, China, 7/1995-6/1997
Electrochemistry, Electroanalytical Technology, Materials for Energy Storage and Conversion, Electrochemical Compression
Major Recognitions and Honors
- Winner of UMD’s invention of the Year for 2015
- Junior Faculty Outstanding Research Award, 2013
- Sigma Xi Research Award, Tennessee Technological University, 2006
- Highly cited researchers from Clarivate Web of Science, 2018, 2019, 2020
Significant Professional Service and Activities
- American Chemical Society
- Materials Research Society
- Electrochemical Society
- American Institute of Chemical Engineers
- Co-Organizer, Eastern Forum of Science and Technology, Forum on Research and Development of Carbon-Based New Energy Materials, Shanghai, China, July 11, 2014.
- Co-leading organizer, Symposium E5, Advanced Materials for Rechargeable Batteries, 2013
- Materials Research Society Fall Meeting & Exhibit, December 1-6, Boston, Massachusetts 2013.
- Co-organizer, B6-Rechargeable Lithium and Lithium Ion Batteries, 218th ECS Meeting, Las Vegas, NV, October 10-15, 2010.
- Co-organizer, Advanced Organic and Inorganic Materials for Electrochemical Power Sources, 217th ECS Meeting, Vancouver, BC, Canada, April 25-30, 2010.
- Co-organizer, Alkaline Electrochemistry in Fuel Cells, 216 ECS Meeting, Vienna, Austria, October 4-9, 2009.
- Lead organizer, Alkaline Electrochemical Power Sources, 213th ECS Meeting, May 18-23, Phoenix, Arizona, 2008.
- Co-founder, Center for Research in Extreme Batteries (CREB), A joint Center of University of Maryland and U.S Army Research Laboratory.
- Associate Editor; ACS APPlied Energy Materials
Dr. Wang’s research activities a wide spectrum of topics ranging from fundamental electrochemistry (electroanalytical technology), to electrochemical devices (Li-ion, Na-ion, Mg-ion batteries, fuel cells and electrochemical compressions), to commercial device demonstration in collaborations with battery manufacturers. Our group emphasize innovation and transformative research by creative thinking to make conventional “impossible” to reality. Using such a “thinking-outside-the-box” approach we have successful expansion of electrochemical stability window for aqueous electrolytes from 1.2V to 3.0V, and use of a single material to fabricate the all-solid-state Li-ion batteries. Dr. Wang and Dr. Kang Xu at Army Research Lab founded a national Center for Research in Extreme Batteries (CREB ), whose members include government Labs, universities, and industries.
1. High energy and safe aqueous batteries
Li-ion batteries using aqueous electrolytes are intrinsically safe and green, but their deployment has been prevented by low energy density imposed by the narrow electrochemical stability window of water. By transplanting the solid-electrolyte-interphase (SEI) concept from non-aqueous Li-ion batteries, Dr. Wang at UMD and Dr. Xu at Army Research Lab (ARL) successfully expanded the electrochemical stability window of aqueous electrolytes from 2.0V to ~4.9 V via forming SEI solid-electrolyte-interphase (SEI) on electrodes, which has been considered unimaginable in battery and electrochemistry community. An intrinsic safe full Li-ion battery of 4.0 V based on such aqueous electrolyte was demonstrated. This new discovery of aqueous SEI sets the foundation for a new direction in aqueous electrochemistry research.
2. Solid state batteries
The kay challenges for the intrinsically safe all-solid-state Li-ion batteries are Li dendrite growth in solid electrolyte and interface/interphase resistance between solid electrolyte and solid active cathode materials due to volume change of active cathode materials. One solution is to use a single material to simultaneously function as anode, cathode and electrolyte in an all-solid-state Li-ion cell, so that the interfacial resistances between electrode and electrolyte was significantly reduced. This concept can be extended to broader applications of other solid-state battery systems, benefiting a high-power, high-energy, long-cycling all-solid-state battery. Current solid ceramic electrolytes promote the Li dendrite growth as evidenced by a lower current for Li dendrite formation in solid state ceramic electrolyte than in liquid electrolytes. The mechanism for Li dendrite formation in solid electrolytes is critical for success of solid state Li-ion batteries.
3. High energy non-aqueous electrolyte
Li metal batteries State-of-the-art Li-ion batteries (LIB) can reach a specific energy of 200-250 Wh kg-1. If the intercalation graphite anode used in LIB can be replaced by Li metal, a Li/NMC cell (NMC: Li(NiMnCo)O2) can deliver a specific energy of 450-500 Wh/kg. However, such Li/NMC batteries would suffer from safety and cycle stability issues caused by the highly reactive nature of Li metal and its tendency of forming dendrite, as well as instability of high Ni-content NMC during charge/discharge cycles. Both issues could be effectively mitigated by the new electrolytes developed by us.
4. Mg-ion and Al-ion batteries
Despite Li ion batteries are experience continuously increment performance improvement since its invention in 1991, its energy density is getting close to theoretical limit. This is because the capacities of both the anode (graphite) and cathode (LiMO2 or LiMPO4 etc) are limited by the maximum Li storage sites. Replacing the intercalation electrode with novel high capacity electrode can dramatically increase the capacity, thus offering new opportunity for high energy batteries. Below gives a comparison of different metal anodes with graphite. As can be seen, Mg and Al offers nearly ten times gravimetric capacity than graphite, and 5-10 times volumetric capacity than graphite. A unique property of Mg and Al metal anode is that due to their slight high reduction potential than Li metal, a thermodynamically stable organic electrolyte can be found, which ensures the interface stability during long cycling.