Columbia University

Stationary electrical energy storage plays several important roles in the U.S. electricity system, and these are expected to grow as the grid continues to evolve. Long-duration energy storage systems address grid needs beyond those covered by daily cycling. Such systems could provide backup power for several days, improving grid resiliency, or allow for the integration of even larger amounts of intermittent renewable sources like wind and solar. In the near term, such systems could help shape the output from individual wind and solar installations, improving the reliability of these resources and thus greatly increasing their value to the grid.

Columbia University's Electrochemical Energy Center will develop a long-duration grid energy storage solution that leverages a new approach to the zinc bromine battery, a popular chemistry for flow batteries. Taking advantage of the way zinc and bromine behave in the cell, the battery will eliminate the need for a separator to keep the reactants apart when charged, as well as allow all the electrolyte to be stored in a single tank, instead of multiple cells. This reduction in “balance of plant” hardware will reduce system cost.

If successful, DAYS projects will provide new forms of long-duration stationary electricity storage systems that enhance grid resiliency, provide low-cost energy capacity, support grid infrastructure, and enable a greater share of intermittent renewable resources in the generation mix.