New Lithium Aqueous Tech - Safer Higher Voltage Power

New Aqueous Battery Tech to Pave Way for Safer Lithium-Ion Batteries

Released November 20, 2015





University of Maryland researchers have devised a novel Water-in-Salt aqueous Lithium ion battery technology that is free from fire risks, poisonous chemicals and environmental hazards – traits common in current Lithium batteries.


Developed along with the U.S. Army Research Laboratory (ARL), the battery could provide power, efficiency and longevity comparable to today’s Lithium-ion batteries. The research demonstrates a major advance in the long history of water-based (aqueous) batteries by doubling the voltage, or power, of an aqueous battery.
According to the researchers, the technology holds great promise, particularly in applications that involve large energies at kilowatt or megawatt levels, such as electric vehicles, or grid-storage devices for energy harvest systems. It could also become an important part of applications where battery safety and toxicity are primary concerns, such as safe, non-flammable batteries for airplanes, naval vessels or spaceships, and in medical devices like pacemakers.
Chunsheng Wang, an associate professor in UMD’s Department of Chemical & Biomolecular Engineering, explained that the technology increased the electrochemical window of aqueous electrolyte from less than 1.5 Volts to ~ 3.0 Volts.


The team also demonstrated high voltage aqueous full Lithium-ion cell with 2.3 Volts, showing for the first time that aqueous batteries could seriously compete in terms of power and energy density with the non-aqueous lithium-ion batteries
From the army’s perspective, the research could lead to thermally, chemically and environmentally safer batteries carried and worn by soldiers; safe, reduced-footprint energy storage for confined spaces – particularly submarines; and novel hybrid power solutions for military platforms and systems.
The key to this breakthrough was the use of a type of water-based electrolyte containing ultrahigh concentrations of a carefully selected Lithium salt.
The approach transformed battery chemistry, resulting in the formation of a thin protective film on the anode electrode for the very first time in a water-based battery. Known in battery science as a Solid Electrolyte Interphase (SEI), such a protective and stabilizing film is essential to the high performance characteristics of state-of-the-art Li-ion batteries. It previously has been achieved only in non-aqueous electrolytes.
The team then compared the performance of their new battery with that of other aqueous battery systems. Results indicated that high stability of other aqueous batteries was achieved only at the expense of voltage and energy density and vice versa.
However, the formation of an anode/electrolyte interphase in the electrolyte allowed the team to break this inverse relationship between cycling stability and high voltage and to achieve both simultaneously.

http://www.forbes.com/sites/jenniferhicks/2015/11/21/a-salty-solution-could-lead-to-safer-lithium-ion-batteries-say-researchers/

http://www.sciencemag.org/content/350/6263/938

http://worldindustrialreporter.com/new-aqueous-battery-tech-to-pave-way-for-safer-lithium-ion-batteries/