Title: Operando Acoustic Monitoring of SEI Formation and Long-Term Cycling in NMC/SiGr Composite Pouch Cells

Abstract

Stable long-term cycling and solid-electrolyte-interphase (SEI) formation are key challenges in the design of Si/graphite composites as Li-ion battery (LIB) anode materials. Typically, these long-term cycling properties are examined in flooded half-cell settings making use of a Li-metal counter electrode and a Si/graphite working electrode. This form factor has the advantage of offering an unlimited supply of Li-ions and electrolyte, thus isolating performance degradation to the passivation of the working electrode. However, half-cell studies are ineffective in revealing performance and degradation mechanisms of the Si/graphite composite in a more commercially realistic full cell setting. This paper outlines an operando acoustic technique that can offer insights on SEI formation and capacity degradation of Si/graphite composites in a full cell setting. Through a combination of electrochemical and chemical analyses, we show that increasing passivation of the silicon particles in the Si/graphite composite anode is correlated with an increase in the acoustic time-of-flight shift. We further show that temporary loss of the acoustic signal during the first cycle is associated with significant gassing of the cell. The operando acoustic technique outlined here is low-cost, simple to setup and has the potential for localized resolution, indicating usefulness in commercial-scale Si/graphite cell quality control andmore » diagnosis.« less

Authors:

Bommier, Clement ^[1]; Chang, Wesley ^[1]; Li, Jianlin  ^[2];

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• Search OSTI.GOV for ORCID "0000-0002-8710-9847"
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Biswas, Shaurjo ^[1]; Davies, Greg ^[1]; Nanda, Jagjit  ^[2];

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• Search OSTI.GOV for ORCID "0000-0002-6875-0057"
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Steingart, Daniel ^[3]

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+ Show Author Affiliations

1. Princeton Univ., NJ (United States)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. Columbia Univ., New York, NY (United States)

Publication Date:

2020-01-21

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE)

OSTI Identifier:

1606671

Grant/Contract Number:  

AC05-00OR22725

Resource Type:

Journal Article: Accepted Manuscript

Journal Name:

Journal of the Electrochemical Society (Online)

Additional Journal Information:

Journal Volume: 167; Journal Issue: 2; Journal ID: ISSN 1945-7111

Publisher:

IOP Publishing

Country of Publication:

United States

Language:

English

Subject:

42 ENGINEERING