A neutron diffraction cell for studying lithium-insertion processes in electrode materials

An electrochemical cell has been constructed for in situ neutron diffraction studies of lithium-insertion/extraction processes in electrode materials for Li-ion batteries. Its key components are a Pyrex tube, gold plated on its inside, which functions as a current collector, and a central lithium rod, which serves as the negative electrode. The device is demonstrated here for a neutron diffraction study of lithium extraction from LiMn2O4: a mechanical Celgard© separator soaked in the electrolyte surrounds the lithium electrode. The LiMn2O4 powder, mixed with electrolyte, occupies the space between separator and current collector.