DoD Scientist of the Quarter

Dr. Kang Xu awarded DoD Scientist of Quarter, recognized for battery materials discovery

An expert leader in the battery materials community, Dr. Kang Xu from the US Army Research Laboratory, Weapons and Materials Directorate, Energetic Materials Science Branch, was recognized for his recent revolutionary scientific discovery of high voltage aqueous electrolyte materials. These new aqueous electrolytes can enable a series of new battery chemistries that have energy density and cycle-life similar to state-of-the-art non­ aqueous Li-ion batteries, but with absolute safety and non-flammability.

Xu’s remarkable research in battery materials led him to find a way to tailor the interphasial chemistry so that water could be stabilized at extreme potentials previously unimaginable. As a result, the narrow electrochemical stability window of water was expanded from 1.23 V to 3.30 V, which can accommodate most energy-dense electrode materials.

Dr. Kang Xu awarded DoD Scientist of Quarter, recognized for battery materials discovery Xu’s work will potentially revolutionize the landscape of the Li-ion battery industry. In the past 25 years, Li-ion batteries provided the highest energy density, but rely on the use of non-aqueous electrolytes that are highly flammable, toxic, and sensitive to ambient moisture. These electrolytes are responsible not only for the fire/explosion hazards often highlighted in headlines, but also for the manufacturing difficulty, the lack of flexibility in form-factors, and for the health concern when close­ and-personal uses are needed. The invention of the high voltage aqueous electrolytes essentially eliminated most of these barriers. This technological advancement would significantly benefit the Army and DoD missions, as the absolute safety removes the concern of using these high-energy batteries in confined spaces such as submarines or cockpits, and dismounted Soldiers carrying diversified power-hungry electronic gadgets will be able to have high energy batteries either integrated into the uniform or configured into wearable formats without safety or health concerns. Additionally, absolutely safe and green electrolytes will allow for the flexible thin-film batteries directly deployed on human skin to power biosensors, while 3D-printing and additive manufacturing at the site of need might become possible due to the elimination of cumbersome and costly moisture-exclusion facilities (such as dry-room and gloveboxes).

Xu was recently given two external awards for his technological achievements: his joint-invention with the University of Maryland on the aqueous electrolyte materials was selected as the "Invention of the Year" in 2016, and more recently, he was selected by the International Battery Association (IBA) as the 2017 recipient for the prestigious Technology Award and was honored at the annual IBA conference in Nara, Japan in March 2017.