Huang, Chun;
Wilson, Matthew D;
Cline, Ben;
Sivarajah, Abeiram;
Stolp, Wiebe;
Boone, Matthieu N;
Connolley, Thomas;
(2025)
Li+ concentration and morphological changes at the anode and cathode interphases inside solid-state lithium metal batteries.
Journal of Physical Energy
, 7
(2)
, Article 025009. 10.1088/2515-7655/adafda.
Preview |
Text
Leung_Li+ concentration and morphological changes at the anode and cathode interphases inside solid-state lithium metal batteries_VoR.pdf Download (2MB) | Preview |
Abstract
Irregular Li heterostructure growth at the interphase between the solid electrolyte and anode reduces solid-state Li metal battery (SSLMB) performance, but the fundamental cause is still elusive. Measuring and imaging Li+ ion diffusion in operando inside an SSLMB using a commercially standard cell configuration are extremely challenging because the ultra-light Li element exhibits a minute signal-to-noise ratio using most x-ray-related characterization methods, and the weak x-ray signals of Li+ are buried by strong signals of other heavy transition metal elements in the cathode and battery enclosure. Here, we pioneer novel operando correlative imaging of coupling x-ray Compton scattering with computed tomography (XCS-CT), which is able to quantify the interplay between spatially resolved Li+ ion diffusion kinetics and Li0 metal structure growth at the interphases of both the anode and cathode sides inside a full-cell SSLMB using a solid polymer electrolyte (SPE) and commercially standard cell configuration during (dis)charging. We show a 61% increase in the efficiency of extracting Li+ ions from the cathode LiNi0.6Mn0.2Co0.2O2 to the anode during charging at 0.1 C compared with at 1 C due to restricted Li+ ion diffusion at the higher rate inside SSLMB. However, this led to the formation of a more irregular interfacial morphology, consisting not only of Li0 dendrites, but also sub-surface pore formation at the anode/SPE interphase. We find that surprisingly, the irregular Li0 structure initiation and growth are accelerated during the first Li stripping step, not the Li plating step, and the root cause is the onset imbalance of Li+ ion diffusion and redox reactions between the anode and cathode. These insights highlight the benefits of asymmetric charging and discharging rates as a promising solution to improving SSLMB performance with SPEs. The operando correlative XCS-CT imaging technique has the potential to study the relationship between active ion concentrations and buried morphological changes for a variety of battery chemistries.
| Type: | Article |
|---|---|
| Title: | Li+ concentration and morphological changes at the anode and cathode interphases inside solid-state lithium metal batteries |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1088/2515-7655/adafda |
| Publisher version: | https://doi.org/10.1088/2515-7655/adafda |
| Language: | English |
| Additional information: | © 2025 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license (https://creativecommons.org/licenses/by/4.0/). |
| Keywords: | solid-state batteries, correlative imaging, lithium ion concentration, microstructure, x-ray Compton scattering, mass transport |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Mechanical Engineering |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10205590 |
Archive Staff Only
 |
View Item |
