Cyclability evaluation on Si based Negative Electrode in Lithium ion Battery by Graphite Phase Evolution: an operando X-ray diffraction study

Abstract

Artificial graphite (FSN) additive is employed as internal structural label for projecting cyclability of Si material native electrode in a mass ratio of Si/FSN = 1.0 in Li ion battery (LIB). Results of operando X-ray diffraction analysis on Si-FSN negative electrode in LIB demonstrate that one can evaluate the lithiation and delithiation affinity of active material by referring phase transition delay of graphite as affected by experimental splits in a formation process of LIB. We prove that a thin layer of surface amorphous structure and residual lattice strain are formed in Si by high energy ball-milling treatment. Those manipulations improve Li intercalation kinetics and thus enabling a capacity fading of less than 10% (from 1860 to 1650 mAhg−1) for Si negative electrode in 50 cycles. Of utmost importance, this study discloses a robust assessment for revealing mechanism on amorphous and strain related silicide formation and predicting cyclability of negative electrode by quantitative phase evolution rate of FSN additive in LIB.

Phase Evolution and Intermittent Disorder in Electrochemically Lithiated Graphite Determined Using in Operando Neutron Diffraction

“…Although graphite is commonly used as a counter electrode to other electrode materials under study using in operando diffraction measurements where some details of LIG phase evolution are given, such as by Hu et al, 33 graphite is not often the focus of discussion. Advances in structural analyses approaches and instrumentation have driven interest in resolving the LIG phase diagram and phase structures, with several authors revisiting the LIG phase evolution using in situ or in operando diffraction.…”

“…Although graphite is commonly used as a counter electrode to other electrode materials under study using in operando diffraction measurements where some details of LIG phase evolution are given, such as by Hu et al, graphite is not often the focus of discussion. Advances in structural analyses approaches and instrumentation have driven interest in resolving the LIG phase diagram and phase structures, with several authors revisiting the LIG phase evolution using in situ or in operando diffraction. ,,,,− While X-rays are predominantly used for these experiments, LIG structure refinement is complicated by the strong preferential orientation of graphitic particles, with the loss of powder average information worsened by the relatively small sample volume being probed.…”

Multiscale Multiphase Lithiation and Delithiation Mechanisms in a Composite Electrode Unraveled by SimultaneousOperandoSmall-Angle and Wide-Angle X-Ray Scattering

“…In this view, scattering methods using lab X-rays, synchrotron radiation, or neutrons are tools of choice because of their high sensitivity to structural and/or composition changes, excellent time and space resolutions, and high penetration into the matter, which allow performing nondestructive operando experiments using representative battery cells. Accordingly, the lithiation/delithiation mechanism of silicon-based electrodes was probed using a wide range of different techniques such as neutron and X-ray reflectivity, − neutron and X-ray radiography, Bragg coherent imaging, tomography, − or diffraction. ,− Recently, the interplay of silicon and graphite in composite electrodes has also been investigated using energy dispersive X-ray diffraction . By following the evolution of the Bragg reflections of the lithiated graphite phases during the charge and discharge of a silicon-graphite/Li half-cell, Yao et al .…”

Using In-Situ Laboratory and Synchrotron-Based X-ray Diffraction for Lithium-Ion Batteries Characterization: A Review on Recent Developments

“…Among all synchrotron techniques used for battery characterization, X-ray diffraction (XRD) is perhaps the most widely applied technique used to analyse the composition and the structure at atomic scale of LIB components [17]. During charge and discharge, electrodes are subject to lithium intercalation and de-intercalation, which result in changes to the lattice parameters, phase changes, and volume contraction/expansion [18][19][20]. Moreover, volume changes can be induced by phase transformation or solid-electrolyte interphase (SEI) formation, inducing strain into the electrodes, which can generate chemical potential changes, capacity fade, and electrode degradation [21,22].…”