Selective Operando Visualization of Ultrathin Lithium in Li-Metal Batteries by Neutron Capture Imaging
Year: 2026
Type: preprint
Abstract: Operando visualization of ultrathin lithium is essential for understanding plating and stripping in lithium-metal batteries, but existing neutron imaging techniques lack sufficient sensitivity for ultra-thin lithium layers formed at crucial early stages. Here we introduce neutron capture imaging (NCI), which selectively detects tritons generated by neutron capture in 6 Li. Ex situ measurements of electrochemically plated and thermally evaporated 6 Li demonstrate sensitivity around 10 nm for a 1.5 h acquisition and two-dimensional imaging with around 100 μm lateral resolution. Simulations indicate that the resolution could approach 25 μm through optical optimization. Operando measurements in an asymmetric Cu|| 6 Li cell reveal spatially heterogeneous lithium plating and stripping in agreement with electrochemical data. Our results establish NCI as a high-sensitivity, near-zero-background tool for operando studies of lithium metal batteries, opening new possibilities for resolving early-stage deposition, dead lithium formation, and interfacial dynamics with broad applicability to ultrathin reactive lithium layers in electrochemical systems.
Source: ChemRxiv
Language: English
Subfield: Radiation
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7220369710