Advanced energy storage promises to play a key role in modernizing our nation’s electricity grid to enable the integration of increasing amounts of renewables, improve operating capabilities, enhance reliability, allow deferral of infrastructure investments and provide backup power during emergencies. Rechargeable lithium (Li)-ion batteries are one of the primary electrochemical storage technologies that provide energy storage for the grid and for electric vehicles. However, Li-ion technology is not without its drawbacks, notably, its electrolyte is flammable. Replacing these liquid electrolytes with a solid-state electrolyte could increase the battery’s abuse tolerance, reduce the need for a battery thermal management system, improve energy density, and lower cost. Solid-state batteries require an ion-conducting (sodium ions in the case of this project) material, that acts as the separator and electrolyte. Innovations to develop suitable materials could help lower the cost and increase the adoption of grid-level energy storage.
Project Innovation + Advantages:
The team led by Iowa State University (ISU) will develop an All Solid-State Sodium Battery (ASSSB) that will have a high energy content, can easily be recycled, and rely on highly abundant and extremely low cost starting materials. Commercially available sodium-based batteries operate at elevated temperatures, which decreases the efficiency and safety of the system. The team seeks to improve all three of the main components of a sodium-based battery: the anode, cathode, and electrolyte separator. The team’s anode is a porous carbon nanotube layer that will serve as a framework on which sodium metal will be deposited. The separator will be made of a novel oxy-thio-nitride glass solid electrolyte, and the cathode will be composed of a polymer in which reversible sodium insertion and removal takes place. The team will need to overcome several challenges, including reducing interfacial resistance between the organic electrode and the solid electrolyte. The proposed sodium battery can operate at room temperature, uses a benign and scalable solid-stack design for a long cycle life, and expects to achieve an energy density eqivalent to state-of-the-art Li-ion cells.
If successful, this flexible solid-state electrolyte could enable much greater deployment of robust batteries for transportation or stationary storage applications, which in turn would allow higher penetration of renewables.
Grid-scale batteries will improve grid resiliency and reduce vulnerability due to outages.
Renewable energy production can be deployed to a greater extent if energy storage technologies are more prevalent.
Low-cost production of solid-state batteries with earth abundant materials could open a large manufacturing industry in the U.S. while providing energy storage that lowers the cost of deploying renewable electricity on the grid.