Lithium isotope enrichment by electrochemical pumping using solid lithium electrolytes

Abstract

Concentrating 6Li isotopes, which exist only approximately 7.6% in nature, to 40 to 90%, is necessary for development of thermal fusion reactors, which are promising as next-generation base-load energy systems. We investigated the possibility of 6Li enrichment by electrochemical pumping using La0.57Li0.29TiO3 solid lithium electrolytes. We also clarified the influence of potential application profiles on separation efficiency. Giving a potential difference to electrodes prepared on both sides of the electrolyte made the electrode on the lithium solution side positive and concentrated 6Li. The efficiency of lithium isotope enrichment was affected by the potential application profile. An intermittent potential application concentrates 6Li with high efficiency. In an intermittent potential application in which the electrode on the lithium solution side was positive, an 6Li concentration with higher efficiency was achieved when a small negative potential was applied to the lithium solution side electrode while suspending application of the positive potential.