DMREF: Design of fast energy storage pseudocapacitive materials

Non-technical Description: Electrical energy storage is essential to the energy transition and to the reduction of greenhouse gas emissions. While electricity storage in batteries has made significant progresses in recent years in terms of the amount of energy stored, one major challenge is the long time required for charging. Capacitors represent another class of electrical energy storage devices that can be charged very quickly.

Such capacitive energy storage is an important technology for numerous applications where electrical energy needs to be stored and/or released quickly. However, current devices and materials can store only a limited amount of energy. The realization of capacitors that could store a large amount of electrical energy could have an enormous impact on energy storage for the electricity grid, for electric mobility solutions, and for consumer electronics.

The project aims at designing novel capacitive materials that can greatly increase the energy storage of electrochemical capacitors with fast charging and discharging. The project’s societal impact lies in its contributions towards the decarbonization of the transportation sector which accounts for 29% of all greenhouse gas emission in the United States today.

The scientific approach will be based on a material design loop including experiments and modeling in order to define the features of capacitive materials enabling high storage ability, in the spirit of the Materials Genome initiative and on a large computational screening of prospective materials to obtain candidates that will be tested experimentally. The project will also serve as a platform for the training of undergraduate and graduate students in topics related to energy storage and modeling.

Advantage will be taken of the existing infrastructure at UCLA and Stanford University to attract talented, ethnically and culturally diverse undergraduate student populations to work on cutting-edge research.

Technical Description: The aim of this research program is to tightly combine experimental and computational methods to identify a new generation of electrochemical energy storage materials based on pseudocapacitance, defined as a charge storage approach which uses fast and reversible surface or near surface redox reactions, and to construct a prototype device integrating the energy storage materials. While the underlying principles of pseudocapacitance are understood, there is currently no ability to predict or design materials that display pseudocapacitive behavior.

A double design loop is proposed. The first one will operate at the atomic scale and will combine first principle electronic structure calculations with synthesis and testing. It will provide thermodynamics and kinetic information to the second level of design that will involve optimization of energy storage device configurations, combining continuum modeling and experimental synthesis and characterization.

From this approach, an energy storage device will be demonstrated based on the developed pseudocapacitive materials. The project will bring fundamental understanding of the factors governing pseudocapacitive material performance and provide practical guidelines for the design of high performance energy storage materials and devices. The research will also have significant scientific merit by establishing the interrelationships among material structure, charge storage dynamics, and charge transfer processes.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.