If fusion power becomes a reality, the world will require significantly more lithium. This is the premise behind Licube, a startup that has licensed technology from Hirosaki University in Japan to purify lithium-6, the specific form of lithium needed for fusion plants to create their own fuel from naturally occurring lithium.
The Need for Lithium in Fusion Power
The fuel supply is critical for the success of fusion power. Most planned fusion plants will operate using a combination of two fuels: deuterium and tritium. While deuterium is readily available, tritium is extremely scarce in nature. It is widely acknowledged in the fusion community that there is not enough tritium to fuel every planned plant.
To address this issue, the proposed solution is to generate tritium on-site within the power plant. A fusion reaction produces a stream of fast-moving particles known as neutrons. Startups intend to encase the reactor in a blanket of lithium, which, when struck by a neutron, splits into helium and tritium. The tritium can then be collected, purified, and reused as fuel in the reactor.
The Challenge of Lithium Separation
Not all lithium is equally effective for this purpose. It exists in two forms: lithium-6 and lithium-7, differentiated by their atomic weights. Lithium-6 is significantly more efficient at capturing neutrons and producing tritium, yet it constitutes only about 7.5% of natural lithium. The separation of these two forms is complex, and current capacity for this process is limited, resulting in a shortage of lithium-6.
