Title: The Chemistry of Electrolyte Reduction on Silicon Electrodes Revealed by in Situ ATR-FTIR Spectroscopy

Abstract

While silicon is the most promising next-generation anode material for lithium-ion batteries (LIBs), silicon electrodes exhibit significant capacity fade with cycling. A common hypothesis is that the capacity loss is due to the solid electrolyte interphase (SEI) forming in the first cycle and becoming destabilized by large cyclic volume changes. A cell for in situ attenuated total reflection-Fourier transform infrared spectroscopy with controllable penetration depth was used to study the chemistry at the electrode–electrolyte interface. The SEI product precursors at the interface were successfully identified and differentiated from free or solvated solvent molecules in the bulk electrolyte. Intriguingly, for the most common electrolyte consisting of ethylene carbonate and diethyl carbonate, ethylene carbonate was found to directly reduce to lithium ethylene dicarbonate on the lithiated silicon surface and diethyl carbonate to selectively reduce to diethyl 2,5-dioxahexane dicarboxylate on the surface of the native silicon-oxide film. In conclusion, understanding this surface dependence of the SEI composition is critical to tuning the silicon electrode surface condition and, ultimately, enhancing the performance of future LIBs.

Authors:

Shi, Feifei  ^[1];

• Search DOE PAGES for author "Shi, Feifei"
• Search DOE PAGES for ORCID "0000-0002-9171-6180"

Ross, Philip N. ^[2]; Somorjai, Gabor A.  ^[3];

• Search DOE PAGES for author "Somorjai, Gabor A."
• Search DOE PAGES for ORCID "0000-0002-8478-2761"

Komvopoulos, Kyriakos  ^[4]

• Search DOE PAGES for author "Komvopoulos, Kyriakos"
• Search DOE PAGES for ORCID "0000-0001-9418-1567"

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+ Show Author Affiliations

1. Univ. of California, Berkeley, CA (United States). Dept. of Mechanical Engineering; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division
2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division
3. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division
4. Univ. of California, Berkeley, CA (United States). Dept. of Mechanical Engineering

Publication Date:

Mon Jun 12 00:00:00 EDT 2017

Research Org.:

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V); USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1418301

Grant/Contract Number:  

AC02-05CH11231

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Physical Chemistry. C

Additional Journal Information:

Journal Volume: 121; Journal Issue: 27; Journal ID: ISSN 1932-7447

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

25 ENERGY STORAGE