LithiumBreeding

Lithium breeding is a concept in fusion energy referring to the production of tritium within a reactor blanket by neutron irradiation of lithium. Tritium is a potential fuel for many deuterium-tritium fusion designs, and breeding aims to provide a self-sustaining tritium supply.

The principal reaction used to breed tritium is Li-6 + n -> T + He-4. Because Li-6 is a minority in natural lithium, enrichment or using lithium-containing materials with higher Li-6 content improves yield. Li-7 can contribute via other neutron reactions but is far less efficient under typical fusion neutron spectra.

Breeding blankets encase the reactor core and contain lithium in ceramic, liquid, or molten-salt form. Common materials include Li2TiO3 ceramics, Li2Be2O3, or lead-lithium eutectic. The blanket absorbs neutrons and heat, breeds tritium, and allows tritium to be extracted through chemical processing or permeation barriers while the reactor continues to operate.

Key challenges include achieving high tritium production with reliable extraction, managing material compatibility under intense neutron and heat flux, and preventing tritium losses and environmental release. Safety, regulatory controls, and remote-handling requirements add further complexity. Ongoing research evaluates different blanket materials, cooling schemes, and tritium-recovery technologies.

In modern fusion programs, tritium breeding is essential for long-term operation. Projects such as ITER and related demonstrations study breeding blankets to validate models of neutron transport, tritium inventory, and integration with energy production. Lithium breeding remains a central area of fusion-blanket design and is the subject of ongoing international collaboration.