The ability to store energy to be used when needed is an essential enabling part of the renewable energy infrastructure. Even being able to shift solar supply by a few hours from peak production (at the middle of the day) to peak demand (late afternoon) can save utilities from turning on expensive peaker plants and burning coal or natural gas.
Electrical Energy Storage
Batteries are currently too expensive and often unable to provide high enough energy or power density to be widely deployed for electrical storage. Advances in materials, and components and at the systems level could rapidly accelerate innovation in this space.
Caltech Professors Robert Grubbs, Brent Fultz, Bill Goddard, Mike Hoffmann, Tom Miller, and Julia Greer are among the group studying materials and processes that make electricity storage work. They are designing new electrode materials and studying the interactions between the chemical reactions that drive performance and the mechanical properties that determine the weight and lifetime of systems. The Caltech teams also have active collaborations with the engineers at JPL with unprecendented capabilities for building battery systems that work in harsh remote environments of space and other planets.
Resnick Fellow Michael Webb, advised by Professors Tom Miller and Zhen-Gang Wang is working toward developing computational methods for the design of enhanced electrolyte solvents in rechargeable batteries. It is a critical problem that even with state-of-the art Lithium ion batteries the electrolyte solvent is typically a flammable mixture of alkyl carbonates. This hazard not only hinders mainstream integration in the transportation industry, but it also virtually eliminates the possibility of using such batteries in grid storage applications. By answering unresolved questions related to ion transport, Mike’s research aims to mitigate many of the safety and performance issues that prevent the use of secondary batteries in high-energy content applications.
Hydrogen is identified as a key player in the sustainable energy economy because it has the potential to provide energy with few environmental impacts. It may also be used as an energy storage medium. However, storing hydrogen is challenging because it is the lightest chemical element and has a very low energy density per unit volume. Conventional storage methods are energy intensive, hence researchers are looking at storage in solids and liquids.
At Caltech, Professors Brent Fultz and Theo Agapie study materials that store hydrogen. Fultz’s recent work includes measuring thermodynamic properties of hydrogen absorption on materials with high surface area and measuring hydrogen gas at high pressures.
Fultz and Agapie advised former Resnick Fellow David Abrecht in his research that focused on the thermodynamic properties of organometallic dihydrogen complexes for hydrogen storage applications. His findings revealed thermodynamic trends that could be useful for the rational design of new hydrogen storage materials.