Lang, Jialiang | Search NASA

DOE OSTI2020

Molten Lithium-Brass/Zinc Chloride System as High-Performance and Low-Cost Battery

Batteries with high safety, low cost, and reasonable energy density are essential for grid-scale energy storage and still remain elusive. In this paper, we report a solid electrolyte-based liquid lithium-brass/zinc chloride (SELL-brass/ZnCl 2 ) battery using garnet-type lithium-ion solid electrolyte, lithium anode, and brass/ZnCl 2 cathode. The chemistry of the cell reaction and the ability of being assembled in discharged state ensures a high safety. The use of low-cost ZnCl 2 cathode can realize a low cell material cost of $16 kWh –1 . The adoption of lithium anode guarantees a high theoretical energy density of 750 Wh kg –1 and 2,250 Wh L –1 . Moreover, by using brass powder as a Zn source in the cathode, the Zn particle growth issue is successfully solved, and a good cycling stability of the battery can be obtained. As full cell performance and scalability are also verified, our SELL-brass/ZnCl 2 battery shows a high potential for practical use in grid energy storage.

25 ENERGY STORAGE↗

DOE OSTI2020

High-purity electrolytic lithium obtained from low-purity sources using solid electrolyte

Lithium (Li) is an important resource for the sustainability of socioeconomic systems given its wide use in various industrial applications. The industrial production of Li metals relies on the electrolysis of a mixture consisting of high-purity lithium chloride (LiCl) and potassium chloride. However, the purification of LiCl is expensive and unsustainable, requiring a substantial amount of energy and the use of noxious chemical reagents, so that producing high-purity Li efficiently and sustainably is a challenge. In this paper we report a new method of producing high-purity electrolytic Li from low-purity LiCl using solid-state electrolyte. Taking advantage of the high Li-ion selectivity of the solid electrolyte, we directly obtained high-purity metallic Li through the electrolysis of low-purity LiCl. Our new method provides two important advantages over conventional methods: (1) the cost of producing high-purity Li is reduced by using low-purity LiCl from low-grade brine, and the simpler purification process reduces the use of energy and chemical reagents; and (2) the operating temperature of the electrolytic process decreases from 400 °C to 240 °C, leading to an additional reduction in energy use.

36 MATERIALS SCIENCE↗