Innovation in Stationary Electricity Storage: The Liquid Metal Battery

Massive electricity storage would offer huge benefits to today’s grid, reducing price volatility, improving stability against loss of power, increasing utilization of generation assets by enabling us to design towards average demand instead of peak demand, and deferring the costs of upgrading existing transmission lines. When it comes to tomorrow’s grid, storage is critical to widespread integration of renewables, i.e., solar and wind, which due to their inherent intermittency present challenges for contribution to base load. Comprising two liquid metals and a molten salt electrolyte, the liquid metal battery has been invented to offer colossal current capability and long service lifetime at very low cost, i.e., the price point of the electricity market. The round-trip efficiency of these batteries is greater than 75% with a duty cycle of 4 h discharge. Fade rates of 0.00009%/cycle have been measured which means retention of >99% of initial capacity after 10 years of daily cycling at full depth of discharge.

Speaker: Donald Sadoway, MIT