Long duration electricity storage (LDES) with 10+ hour cycle duration is an economically competitive option to accelerate the penetration of renewable energy into the utility market. Unfortunately, none of the available energy storage technologies can meet the LDES’ requirements for duration and cost. We here report a focused kinetic study on Fe-oxide reduction process, which is a key step for solid oxide iron-air battery; the latter has been recently demonstrated as a LDES compatible battery. The study clearly shows that Ir is an excellent catalyst to boost the sluggish Fe-oxide reduction kinetics.
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Demonstration of 10+ hour energy storage with ϕ1′′ laboratory size solid oxide iron–air batteries
Long duration electricity storage (LDES) with 10+ hour cycle duration is an economically competitive strategy to accelerate the penetration of renewable energy into the utility market. Unfortunately, none of the available energy storage technologies can meet the LDES requirements in terms of duration and cost. The newly emerged solid-oxide iron–air batteries (SOIABs) with energy-dense solid iron as an energy storage material have inherent advantages for LDES applications. Herein, we report for the first time the LDES capability of SOIABs even at a laboratory scale. We show that SOIABs with an Ir-catalyzed Fe-bed can achieve excellent energy density (625 W h kg −1 ), long cycle duration (12.5 h) and high round-trip efficiency (∼90%) under LDES-related working conditions. Given the excellent low-rate performance and the use of earth-abundant, low-cost Fe as an energy storage material, we conclude that the SOIAB is a well-suited battery technology for LDES applications.
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- Award ID(s):
- 1801284
- PAR ID:
- 10437730
- Date Published:
- Journal Name:
- Energy & Environmental Science
- Volume:
- 15
- Issue:
- 11
- ISSN:
- 1754-5692
- Page Range / eLocation ID:
- 4659 to 4671
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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