Transportation Storage

Iowa State University (ISU) will develop new lithium-ion-conducting glassy solid electrolytes to address the shortcomings of present-day lithium batteries. The electrolytes will have high ionic conductivities and excellent mechanical, thermal, chemical, and electrochemical properties. Because glasses lack grain boundaries, they will also be impermeable to lithium dendrites, branchlike metal fibers that can short-circuit battery cells. These glassy solid electrolytes can enhance the safety, performance, manufacturability, and cost of lithium batteries.

24M Technologies will lead a team to develop low cost, durable, enhanced separators/solid state electrolytes to build batteries using a lithium metal anode. Using a polymer/solid electrolyte ceramic blend, 24M will be able to make a protective layer that will help eliminate side reactions that have previously contributed to performance degradation and provide a robust mechanical barrier to branchlike metal fibers called dendrites. Unimpeded, dendrites can grow to span the space between the negative and positive electrodes, causing a short-circuit.

American Manufacturing, in collaboration with the University of Colorado at Boulder, will develop a flash sintering system to manufacture solid lithium-conducting electrolytes with high ionic conductivity. Conventional sintering is the process of compacting and forming a solid mass by heat and/or pressure without melting it to the point of changing it to a liquid, similar to pressing a snowball together from loose snow. In conventional sintering a friable ceramic “bisque” is heated for several hours at very high temperatures until it becomes dense and strong.

Oak Ridge National Laboratory (ORNL) will develop glassy Li-ion conductors that are electrochemically and mechanically stable against lithium metal and can be integrated into full battery cells. Metallic lithium anodes could significantly improve the energy density of batteries versus today’s state-of-the-art lithium ion cells. ORNL has chosen glass as a solid barrier because the lack of grain boundaries in glass mitigates the growth of branchlike metal fibers called dendrites, which short-circuit battery cells.

The team at the California Institute of Technology (Caltech) has developed a method to determine the mechanical properties of lithium as a function of size, temperature, and microstructure. The body of scientific knowledge on these properties and the way dendrites form and grow is very limited, in part due to the reactivity of metallic lithium with components of air such as water and carbon dioxide. The team proposes to conduct a targeted investigation on the properties of electrodeposited lithium metal in commercial thin-film solid-state batteries.

The Citrine Informatics team is demonstrating a proof-of-concept for a system that would use experimental work to intelligently guide the investigation of new solid ionic conductor materials. If successful, the project will create a new approach to material discovery generally and new direction for developing promising ionic conductors specifically.

Cornell University will develop a new type of rechargeable lithium metal battery that provides superior performance over existing lithium-ion batteries. The anode, or negative side of a lithium-ion battery, is usually composed of a carbon-based material. In lithium metal batteries, the anode is made of metallic lithium. While using metallic lithium could result in double the storage capacity, lithium metal batteries have unreliable performance, safety issues, and premature cell failure. There are two major causes for this performance degradation.

The University of California, San Diego (UC San Diego) is developing an early-stage concept for an advanced electrochemical energy storage system. If successful, the new approach would enable higher-energy density and higher-power systems that are able to operate over a much wider temperature and voltage range than today’s technologies. Similar to how water is used as a suspension medium for the acid in a conventional lead-acid car battery, the research team is studying the use of certain gases liquefied under pressure as solvents in novel electrolyte systems.

Cree Fayetteville will develop high voltage (10kV), high energy density (30 J/cm3), high temperature (150 °C+) capacitors utilizing chemical vapor deposition (CVD) diamond capable of powering the next generation of high-performance power electronics systems. CVD diamond is a superior material for capacitors due to its strong electrical, mechanical, and materials qualities that are inherently stable over varying temperatures. It also has similar qualities of single crystal diamond without the high cost.

United Technologies Research Center (UTRC) is developing a new climate-control system for EVs that uses a hybrid vapor compression adsorption system with thermal energy storage. The targeted, closed system will use energy during the battery-charging step to recharge the thermal storage, and it will use minimal power to provide cooling or heating to the cabin during a drive cycle. The team will use a unique approach of absorbing a refrigerant on a metal salt, which will create a lightweight, high-energy-density refrigerant.