Grid-level Electricity Storage

 

It has long been understood that if batteries were able to achieve the price and energy storage performance of fossil fuels, the world would be a vastly different place. We would drive cleaner vehicles, the word “intermittency” would not come up in conversations about renewables and the grid, geopolitics in volatile oil producing regions of the world would be transformed, and the U.S. would benefit from an expansive, sustainable clean-energy-based economy. There is not an energy related problem with higher stakes than storage, and a breakthrough in battery development would have enduring global impact. For these reasons we pursue new battery and storage designs and concepts, that are safe, affordable, scalable and built from domestic, earth-abundant raw materials.

The Liquid Metal Battery project is developing a low-cost, long-lifespan battery for grid-scale stationary storage. The battery comprises three liquid layers: on the bottom a high-density liquid metal acting as the positive electrode, on the top a low-density liquid metal acting as the negative electrode, and in between the two metal layers a molten salt of intermediate density acting as the electrolyte. Owing to the rank order of their densities and the immiscibility of contiguous phases, the three liquid layers self assemble without the need for membranes or separators. This suggests that the design will be scalable at low cost. Furthermore, common failure mechanisms found in solid electrodes are inoperative in liquid electrodes which translates into a long service lifetime.

Current research efforts encompass a wide range of scientific topics and engineering challenges, including fundamental thermodynamic measurements of candidate electrode couples, computational thermal modeling, electrochemical studies of molten salt electrolytes, long term corrosion and lifespan testing, characterization of single-cell batteries, and scaling up the design to build larger cells and, ultimately, multi-cell batteries.

The on-campus research has been funded by ARPA-E (Advanced Research Projects Agency – Energy) and the French energy company, Total, as well as seed funds from the Deshpande Center at MIT, the Chesonis Family Foundation at MIT, DARPA (Defense Advanced Research Projects Agency), the Massachusetts Clean Energy Center, and Lightspeed Ventures.

In parallel, scale-up to commercial product is being pursued at Ambri  (formerly Liquid Metal Battery Corporation), a start-up company co-founded by Sadoway with two of his former students, David Bradwell and Luis Ortiz. Funding for Ambri comes from Bill Gates, Total, and Khosla Ventures.

 

Recent publications on the topic:

  • S. Poizeau and D.R. Sadoway, “Application of the Molecular Interaction Volume Model (MIVM) to calcium-based liquid alloys of systems forming high-melting intermetallics,” J. Am. Chem. Soc., 135(22), 8260-8265 (2013).
  • H. Kim, D.A. Boysen, T. Ouchi, and D.R. Sadoway, “Calcium-Bismuth Electrodes for Large-Scale Energy Storage (Liquid Metal Batteries),” J. Power Sources, 241, 239-248 (2013).
  • J.M. Newhouse, S. Poizeau, H. Kim, B.L. Spatocco, and D.R. Sadoway, “Thermodynamic properties of calcium–magnesium alloys determined by emf measurements,” Electrochim. Acta, 91, 293-301 (2013).
  • H. Kim, D.A. Boysen, J.M. Newhouse, B.L. Spatocco, B. Chung, P.J. Burke, D.J. Bradwell, K. Jiang, A.A. Tomaszowska , K. Wang, W. Wei , L.A. Ortiz , S.A. Barriga , S.M. Poizeau , and D.R. Sadoway, “Liquid Metal Batteries: Past, Present, and Future,” Chem. Rev., 113 (3), 2075-2099 (2013), doi: 10.1021/cr300205k (2012).
  • S. Poizeau, H. Kim, J.M. Newhouse, B.L. Spatocco, and D.R. Sadoway, “Determination and modeling of the thermodynamic properties of liquid calcium–antimony alloys,” Electrochim. Acta, 76, 8-15 (2012).
  • D.J. Bradwell, H. Kim, A.H.C. Sirk and D.R. Sadoway, “Magnesium-antimony liquid metal battery for stationary energy storage,” J. Am. Chem. Soc., 134 (4), 1895-1897 (2012).
  • H. Kim, D.A. Boysen, D.J. Bradwell, B. Chung,  K. Jiang, A.A. Tomaszowska, K. Wang, W. Wei, and D.R. Sadoway, “Thermodynamic Properties of Calcium-Bismuth Alloys Determined by Emf Measurements,” Electrochim. Acta, 60, 154-162 (2012).
  • S. Poizeau, H. Kim, J.M. Newhouse, B.L. Spatocco, and D.R. Sadoway, “Determination and modeling of the thermodynamic properties of liquid calcium–antimony alloys,” Electrochim. Acta, 76, 8-15 (2012).
  • D.J. Bradwell, S. Osswald, W. Wei, S.A. Barriga, G. Ceder, and D.R. Sadoway, “Recycling ZnTe, CdTe, and other compound semiconductors by ambipolar electrolysis,” J. Am. Chem. Soc., 133, 19971–19975 (2011).