SBIR Phase I: Low Cost Metal Chelate Flow Battery for Long Duration Energy Storage

Otoro Energy Inc, Boulder CO

Investigators

Abstract

This Small Business Innovation Research (SBIR) Phase I project develops the chemistry for a new flow battery used to store energy for the electric grid. The battery chemistry uses abundant minerals and materials that can be sourced and manufactured in the United States. These flow battery materials support long duration energy storage of 4 to 100 hours – enough to back up the grid and support increased use of intermittent power sources such as solar and wind. This flow battery technology aims to meet aggressive cost targets for grid-scale storage, positioning the company to take advantage of the domestic and international market demand for energy storage. The battery system provides an opportunity for the U.S. to own high impact battery technology and claim a leadership position in the long duration energy storage market. This SBIR Phase I project seeks to lower the materials costs of a metal chelate flow battery for 10+ hour storage durations with greater than 80% round-trip efficiency. The goal is to develop a material purification process that uses low-grade minerals and removes key impurities with minimal waste. This goal will be achieved through the development and construction of a chemical purification system that selectively removes the impurities present in the low-grade minerals. The process will be validated by the demonstration of a flow battery operating with 10+ hours of continuous discharge at full power. The research and development effort focuses on a holistic solution to flow battery performance via a new chemistry that optimizes cost, abundance, safety, and performance in a single platform for long duration energy storage. Areas of development include electrolyte purity, sensitivity to precursors, processes development, system fouling and electrolyte purity sensitivity, purification system design and recycling, and 10-24 hour discharge battery performance demonstration incorporating the new purification process. 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.