Investigating Surface and Interface Phenomena in LiFeBO3 Electrodes Using Photoelectron Spectroscopy Depth Profiling

Julia Maibach, Reza Younesi, Nele Schwarzburger, Mihaela Gorgoi, Maximilian Fichtner, Kristina Edström

Research output: Contribution to journalConference abstract in journalResearchpeer-review

Abstract

The formation of surface and interface layers at the electrodes is highly important for the performance and stability of lithium ion batteries. To unravel the surface composition of electrode materials, photoelectron spectroscopy (PES) is highly suitable as it probes chemical surface and interface properties with high surface sensitivity. Additionally, by using synchrotron-generated hard x-rays as excitation source, larger probing depths compared to in-house PES can be achieved. Therefore, the combination of in-house soft x-ray photoelectron spectroscopy and hard x-ray photoelectron spectroscopy (HAXPES) enables reliable and non-destructive depth profiling. Thus, detailed investigation of compositional gradients at electrode surfaces and interfaces from a sub-monolayer to several nanometer length scales can be performed. As this depth region is especially relevant for both electronic and ionic transport processes, the presented combinatorial approach is a very valuable tool in characterizing battery electrodes and their interfaces. We apply this technique to lithium iron borate (LiFeBO3) battery electrodes at different cycling conditions to study the surface and interface layer evolution. Due to its high theoretical capacity (220 mA h g-1) LiFeBO3 is a promising cathode material for lithium ion batteries. However, its application is limited because of significant degradation due to surface reactions upon exposure to moisture and air. Therefore, detailed compositional characterization of LiFeBO3 electrode surfaces is essential to gain further understanding of the degradation processes. To study these properties for the pristine material, the electrode fabrication conditions were carefully controlled to limit contact to air and moisture. The investigation of the iron valence state in dependence of the electrode preparation as well as cycling conditions is presented as higher valence states of iron are most likely involved in the degradation process.
Original languageEnglish
JournalElectrochemical Society. Meeting Abstracts (Online)
VolumeMA2014-02
Pages (from-to)242
Number of pages1
ISSN2151-2043
Publication statusPublished - 2014
Event226th Meeting of the Electrochemical Society (ECS) and 7th Meeting of the Mexico Section of the Electrochemical Society ECS and SMEQ Joint International Meeting : Joint international meeting - Cancun, Mexico
Duration: 5 Oct 20149 Oct 2014
Conference number: 226

Conference

Conference226th Meeting of the Electrochemical Society (ECS) and 7th Meeting of the Mexico Section of the Electrochemical Society ECS and SMEQ Joint International Meeting
Number226
CountryMexico
CityCancun
Period05/10/201409/10/2014

Keywords

  • Electrochemical Interfaces in Energy Storage Systems IV - Oct 7 2014 2:00PM

Fingerprint Dive into the research topics of 'Investigating Surface and Interface Phenomena in LiFeBO3 Electrodes Using Photoelectron Spectroscopy Depth Profiling'. Together they form a unique fingerprint.

Cite this