Neutron Depth Profiling (NDP) is an analytical neutron technique that continues to grow in popularity for the quantification of Li ions in lithium-ion battery (LIB) materials. Most investigations occur at high flux neutron sources, i.e. cold or thermal neutron beam facilities, offered by high-power (10-20 MW) research reactors and employing multiple NDP energy and concentration standards. This work aims to develop a feasible method using NDP facilities with less intense neutron flux at lower power research reactors to quantitatively determine the Li concentration in LIB materials, while also applying a “thick” energy and concentration standard. Here, we describe a methodology for processing and calibrating NDP data collected using a multi-detector (i.e., 7-detector setup), which is essential to increase the detection efficiency. The Li concentration of a Li6PS5Cl0.5Br0.5 solid-state electrolyte was determined to be 2.2×1022 Li atoms cm−3. This value deviated by less than 3% of the expected Li atom concentration using a “thick” LiF single crystal wafer as a concentration standard. The method described in this work can be applied to other low-power reactors and other NDP-sensitive isotopes to further increase the application and availability of user-based NDP facilities.
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