Visualizing Lithium Ion Transport in Solid‐State Li–S Batteries Using ⁶Li Contrast Enhanced Neutron Imaging

Abstract

The elucidation of lithium ion transport pathways through a solid electrolyte separator is a vital step toward development of reliable, functional all‐solid‐state batteries. Here, advantage has been taken of the significantly higher neutron attenuation coefficient of one of the most abundant stable isotopes of lithium, 6Li, with respect to that of naturally occurring lithium isotope mixture, to perform neutron imaging on a purpose built all‐solid‐state lithium–sulfur battery. Increasing the 6Li content in the anode while using natural lithium in the solid electrolyte separator and the cathode enhances the contrast such that it is possible to differentiate, during the initial discharge, between the mobile lithium ions diffusing through the cell from the anode and those that are initially located in the solid electrolyte. The sensitivity of neutrons to the different lithium isotopes means that operando neutron radiography allows demonstration of the lithium ion diffusion through the cell while in situ neutron tomography has permitted presentation, in three dimensions, of the distribution of the trapped lithium ions inside the cell in charged and discharged states.

Insight into Dendrites Issue in All Solid‐State Batteries with Inorganic Electrolyte: Mechanism, Detection and Suppression Strategies

“…reported using Li isotope contrast‐enhanced neutron imaging to visualize lithium‐ion transport in the Li‐S solid‐state battery. [ 64 ] Neutron depth profiling (NDP) can also directly show the lithium distribution information along the depth direction. Through dynamic monitoring of the lithium plating process, lithium concentration reveals the LD propagation state.…”

Tracking the Initial Capacity Loss in Solid-State Batteries using in-situ Neutron Tomography and Raman Imaging

“…Thereby allowing for a better understanding of the interfacial instability and its contribution to capacity loss, especially during initial charge/discharge cycles. 15 Herein, by using neutron computed tomography, we trace in situ lithium displacement in an allsolid-state battery composed of a 7 Li anode, nat Li3PS4(LPS) electrolyte, and a nat LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode. nat Li denotes the isotopic distribution encountered in natural Li sources.…”