Redox oscillations in 18650-type lithium-ion cell revealed by in operando Compton scattering imaging

TL;DR

This study employs in-operando Compton scattering imaging to visualize and analyze inhomogeneous lithiation patterns and their oscillations in 18650-type lithium-ion batteries during charge-discharge cycles.

Contribution

It introduces a novel application of high-energy synchrotron x-ray Compton scattering imaging to observe real-time lithiation dynamics in commercial lithium-ion batteries.

Findings

Inhomogeneous lithiation patterns emerge during cycling.

Lithiation patterns exhibit oscillations synchronized with charging.

The dominant oscillation period matches the charging time scale.

Abstract

Compton scattering imaging using high-energy synchrotron x-rays allows the visualization of the spatio-temporal lithiation state in lithium-ion batteries probed in-operando. Here, we apply this imaging technique to the commercial 18650-type cylindrical lithium-ion battery. Our analysis of the lineshapes of the Compton scattering spectra taken from different electrode layers reveals the emergence of inhomogeneous lithiation patterns during the charge-discharge cycles. Moreover, these patterns exhibit oscillations in time where the dominant period corresponds to the time scale of the charging curve.