Novel Polymer Electrolyte
Demand for Lithium-ion (Li-ion) batteries has increased significantly as products such as smartphones, laptops, electric vehicles, and grid storage batteries rise in popularity. However, Li-ion batteries have numerous safety and performance limitations due to their flammable electrolyte and the charge storage density of their active materials, which are not easily overcome by incremental progress. New types of high-performance separators and electrodes built with solid-state ion conductors could simultaneously improve the energy density and safety of lithium ion batteries by removing the most flammable battery components, and also improving the driving range and durability of electric vehicles. Solid-state separators also open the door to the use of lithium metal as an active material, resulting in a significant increase in cell energy content, and the subject of research efforts for the past several decades. New battery technology that employs energy dense, thermally stable, and long-lasting materials will also be of interest for grid storage, particularly in dense, urban environments where the space occupied by storage systems is more of a concern.
Project Innovation + Advantages:
Ionic Materials will develop a lithium metal (not lithium ion) rechargeable battery cell that employs a novel solid polymer electrolyte that enables the world’s first truly safe lithium metal rechargeable battery cell. Scientists at the City University of New York have found that Ionic Material’s proprietary ionic conducting polymer is the most highly lithium conducting solid state polymer material ever measured (at room temperature). This polymer has high ionic conductivity across a range of temperatures, can be reliably extruded into very thin films, is non-flammable, has attractive mechanical properties, and is compatible with a variety of different anodes and cathodes, including lithium metal. This polymer also has the potential to address a number of challenges associated with lithium metal anodes, including electrochemical stability and the ability to cycle without the growth of branchlike metal fibers called dendrites. If left unimpeded, dendrites can grow to span the space between the negative and positive electrodes, causing short-circuiting. Ionic Materials' polymer electrolyte will eliminate the risk of battery shorting due to dendrites, and speed the safe implementation of solid-state, lithium metal anode batteries. Such cells are of particular interest due to their extremely high specific energy (400 Wh/kg or more versus 285 Wh/kg for the best Li-Ion cells today) and their potential to reduce cell costs below $100/kWh, a commonly cited tipping point for the mass adoption of electric vehicles.
If successful, developments made under the IONICS program will increase the energy storage content for vehicle batteries by about 30% compared to today's Li-ion batteries and significantly reduce battery storage system costs.
IONICS program innovations could contribute to energy storage solutions for transportation and the grid, lessening U.S. dependence on imported oil and improving grid resilience.
A 10% increase in electric vehicle use would reduce US oil consumption by 3% and reduce total US CO2 emissions by 1%.
IONICS program innovations could further establish U.S. businesses as technical leaders in energy storage, encouraging greater use of readily available renewable resources and increasing the competitiveness of electric vehicles.CONTACTS
ARPA-E Program Director:
Dr. Halle CheesemanProject Contact:
Press and General Inquiries Email:
ARPA-E-Comms@hq.doe.govProject Contact Email:
Carnegie Mellon University