Transportation Storage

Gas Technology Institute (GTI) is developing a natural gas tank for light-duty vehicles that features a thin, tailored shell containing microscopic valves which open and close on demand to manage pressure within the tank. Traditional natural gas storage tanks are thick and heavy, which makes them expensive to manufacture. GTI's tank design uses unique adsorbent pellets with nano-scale pores surrounded by a coating that functions as valves to help manage the pressure of the gas and facilitate more efficient storage and transportation.

General Electric (GE) Global Research is developing a low-cost, at-home natural gas refueling system that reduces fueling time and eliminates compression stages. Traditional compressor-based natural gas refueling systems require removal of water from natural gas through complicated desiccant cycles to avoid damage. GE's design uses a chiller to cool the gas to a temperature below -50°C, which would separate water and other contaminants from the natural gas. This design has very few moving parts, will operate quietly, and will be virtually maintenance-free.

PolyPlus Battery Company, in collaboration with SCHOTT Glass, will develop flexible, solid-electrolyte-protected lithium metal electrodes made by the lamination of lithium metal foil to thin solid electrolyte membranes that are highly conductive. Past efforts to improve lithium cycling by moving to solid-state structures based on polycrystalline ceramics have found limited success due to initiation and propagation of dendrites, which are branchlike metal fibers that short-circuit battery cells.

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).

Sila Nanotechnologies will develop solid-state ceramic lithium batteries with high energy density. Traditional methods using ceramic electrolytes significantly reduces a battery’s volumetric energy density because the materials are relatively bulky. Commercially produced separator membranes are also expensive and thick because of challenges in fabrication and handling of thinner, defect-free solid-state electrolyte membranes. In addition, such membranes are often air sensitive, have low ionic conductivity, and are susceptible to the growth of branchlike metal fibers called dendrites.

The University of Delaware (UD) with their project partners will develop a new class of hydroxide exchange membranes (HEMs) for use in electrochemical devices such as fuel cells. Hydroxide exchange membrane fuel cells (HEMFC), in contrast to PEM fuel cells, can use catalysts based on low-cost metals as well as inexpensive membranes and bipolar plates. However, a low-cost HEM that simultaneously possesses adequate ion conductivity, chemical stability, and mechanical robustness does not yet exist.

Pennsylvania State University (Penn State) will develop a process for cold-sintering of ceramic ion conductors below 200°C to achieve a commercially viable process for integration into batteries. Compared to liquid electrolytes, ceramics and ceramic composites exhibit various advantages, such as lower flammability, and larger electrochemical and thermal stability. One challenge with traditional ceramics is the propagation of lithium dendrites, branchlike metal fibers that short-circuit battery cells.

3M will develop a new anion exchange membrane (AEM) technology with widespread applications in fuel cells, electrolyzers, and flow batteries. Unlike many proton exchange membrane (PEM) applications, the team’s AEM will operate in an alkaline environment, which means lower-cost electrodes can be used. The team plans to engineer a membrane that simultaneously meets key goals for resistance, mechanical and chemical stability, and cost. They will do this by focusing on simple, hydroxide-stable polymers, such as polyethylene, and stable cations, such as tetraalkylammonium and imidazolium groups.

The University of California, San Diego (UC San Diego), in partnership with Liox Power and the University of Maryland, will develop a self-forming, high temperature solid-state lithium battery that solves the critical cost and performance problems impeding commercialization of solid-state batteries for electric vehicles. The battery will possess a very long life due to a chemical mechanism that repairs cycling damage automatically. This self-healing electrolyte will also limit the growth of dendrites.

United Technologies Research Center (UTRC) will develop a redox flow battery system that combines next-generation reactants with an inexpensive and highly selective membrane. This SMART-FBS project addresses the two highest cost components in redox flow battery systems: reactants and membranes. The team plans to develop these two components simultaneously using core materials that will work in tandem. Polymer membranes will be developed that include benzimidazole or pyridine structures; ionic conductivity will come from the membrane’s structure that allows acid to be imbibed into the polymer.