Energy storage devices based on Lithium-air flow systems for electric grid applications

Florida State University, Tallahassee FL

Investigators

Abstract

Renewable sources of electric power such as wind and solar power produce output that is constantly fluctuating in time, sometimes by more than one order of magnitude within a few minutes or hours. At penetrations larger than 20%, these fluctuations require high capacity energy storage devices that are environmentally friendly, reliable, and do not compromise the security of the national electricity grid. To address this issue, the current project introduces fundamental advances in the theoretical understanding, modeling, simulation, experimental characterization and development of Lithium-air flow systems for grid applications. The proposed systems are tailored to large-scale grid applications by being cost effective and having a high energy density and long cycle life in comparison with current electrical energy storage systems used in grid applications. The proposed systems will also represent an attractive technology for building low-cost batteries for electric vehicles, by having a design that allows fast fueling by simply changing the electrolyte with pure water and replacing the anode electrode. The goal of this proposal is to develop innovative Li-air systems that can be scaled up and used in grid applications. The energy and power ratings of the proposed systems are independently adjustable, making the proposed batteries attractive for building high-capacity and low-cost energy storage devices. The research component focuses on understanding the fundamental science and developing the technology for metal-air electrochemical systems for large and scalable energy storage applications. The novelty of the approach lies its strong emphasis on: (1) The combined theoretical-experimental investigation of the material properties and processes in Li-air flow batteries with cathodes made of layers of buckypaper with variable porosity and catalyst deposition; (2) An innovative design for Li-air flow batteries with energy densities over 250 Wh/kg, and minimum cost. The electrochemical reaction unit of the cell (which consists of the metal anode, separator and the porous cathode) is separated from the oxygen exchange and electrolyte storage units, allowing for easy transportation, installation, and scalability of the system; and (3) Computational optimization of the porosity and catalyst distributions, and experimental development of a prototype cell. The education component focuses on the development of a Virtual Battery Laboratory - a simulation package for metal-air batteries that incorporates the theoretical models into a user-friendly battery and circuit simulator. A new Graduate Certificate Program in Renewable Energy and Energy Storage Systems, primarily addressing people from the industry will be developed, and a 2-week module on the electrochemical modeling and simulation of lithium and other metal-based batteries will be incorporated into the undergraduate and graduate curricula at Florida A&M University and Florida State University.