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Title: Mechanical measurements on lithium phosphorous oxynitride coated silicon thin film electrodes for lithium-ion batteries during lithiation and delithiation

Abstract

The development of large stresses during lithiation and delithiation drives mechanical and chemical degradation processes (cracking and electrolyte decomposition) in thin film silicon anodes that complicate the study of normal electrochemical and mechanical processes. To reduce these effects, lithium phosphorous oxynitride (LiPON) coatings were applied to silicon thin film electrodes. Applying a LiPON coating has two purposes. First, the coating acts as a stable artificial solid electrolyte interphase. Second, it limits mechanical degradation by retaining the electrode's planar morphology during cycling. The development of stress in LiPON-coated electrodes was monitored using substrate curvature measurements. LiPON-coated electrodes displayed highly reproducible cycle-to-cycle behavior, unlike uncoated electrodes which had poorer coulombic efficiency and exhibited a continual loss in stress magnitude with continued cycling due to film fracture. The improved mechanical stability of the coated silicon electrodes allowed for a better investigation of rate effects and variations of mechanical properties during electrochemical cycling.

Authors:
;  [1]; ;  [2];  [3];  [2];  [4]
  1. Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)
  2. Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)
  3. (HIU), Helmholtzstraße 11, 89081 Ulm (Germany)
  4. (Hong Kong)
Publication Date:
OSTI Identifier:
22590544
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANODES; COATINGS; EFFICIENCY; ELECTROCHEMISTRY; FRACTURES; LITHIUM; LITHIUM ION BATTERIES; LITHIUM IONS; MECHANICAL PROPERTIES; MORPHOLOGY; NITRIDES; OXYGEN COMPOUNDS; SILICON; SOLID ELECTROLYTES; STABILITY; STRESSES; SUBSTRATES; THIN FILMS

Citation Formats

Al-Obeidi, Ahmed, E-mail: alobeidi@mit.edu, Thompson, Carl V., E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu, Kramer, Dominik, E-mail: dominik.kramer@kit.edu, Mönig, Reiner, E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu, Helmholtz Institute Ulm for Electrochemical Energy Storage, Boles, Steven T., E-mail: steven.t.boles@polyu.edu.hk, and Hong Kong Polytechnic University, 11 Yuk Choi Rd, Hung Hom. Mechanical measurements on lithium phosphorous oxynitride coated silicon thin film electrodes for lithium-ion batteries during lithiation and delithiation. United States: N. p., 2016. Web. doi:10.1063/1.4961234.
Al-Obeidi, Ahmed, E-mail: alobeidi@mit.edu, Thompson, Carl V., E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu, Kramer, Dominik, E-mail: dominik.kramer@kit.edu, Mönig, Reiner, E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu, Helmholtz Institute Ulm for Electrochemical Energy Storage, Boles, Steven T., E-mail: steven.t.boles@polyu.edu.hk, & Hong Kong Polytechnic University, 11 Yuk Choi Rd, Hung Hom. Mechanical measurements on lithium phosphorous oxynitride coated silicon thin film electrodes for lithium-ion batteries during lithiation and delithiation. United States. doi:10.1063/1.4961234.
Al-Obeidi, Ahmed, E-mail: alobeidi@mit.edu, Thompson, Carl V., E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu, Kramer, Dominik, E-mail: dominik.kramer@kit.edu, Mönig, Reiner, E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu, Helmholtz Institute Ulm for Electrochemical Energy Storage, Boles, Steven T., E-mail: steven.t.boles@polyu.edu.hk, and Hong Kong Polytechnic University, 11 Yuk Choi Rd, Hung Hom. 2016. "Mechanical measurements on lithium phosphorous oxynitride coated silicon thin film electrodes for lithium-ion batteries during lithiation and delithiation". United States. doi:10.1063/1.4961234.
@article{osti_22590544,
title = {Mechanical measurements on lithium phosphorous oxynitride coated silicon thin film electrodes for lithium-ion batteries during lithiation and delithiation},
author = {Al-Obeidi, Ahmed, E-mail: alobeidi@mit.edu and Thompson, Carl V., E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu and Kramer, Dominik, E-mail: dominik.kramer@kit.edu and Mönig, Reiner, E-mail: reiner.moenig@kit.edu, E-mail: cthomp@mit.edu and Helmholtz Institute Ulm for Electrochemical Energy Storage and Boles, Steven T., E-mail: steven.t.boles@polyu.edu.hk and Hong Kong Polytechnic University, 11 Yuk Choi Rd, Hung Hom},
abstractNote = {The development of large stresses during lithiation and delithiation drives mechanical and chemical degradation processes (cracking and electrolyte decomposition) in thin film silicon anodes that complicate the study of normal electrochemical and mechanical processes. To reduce these effects, lithium phosphorous oxynitride (LiPON) coatings were applied to silicon thin film electrodes. Applying a LiPON coating has two purposes. First, the coating acts as a stable artificial solid electrolyte interphase. Second, it limits mechanical degradation by retaining the electrode's planar morphology during cycling. The development of stress in LiPON-coated electrodes was monitored using substrate curvature measurements. LiPON-coated electrodes displayed highly reproducible cycle-to-cycle behavior, unlike uncoated electrodes which had poorer coulombic efficiency and exhibited a continual loss in stress magnitude with continued cycling due to film fracture. The improved mechanical stability of the coated silicon electrodes allowed for a better investigation of rate effects and variations of mechanical properties during electrochemical cycling.},
doi = {10.1063/1.4961234},
journal = {Applied Physics Letters},
number = 7,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
  • We report real-time average stress measurements on composite silicon electrodes made with two different binders – viz. Carboxymethyl cellulose (CMC) and Polyvinylidene fluoride (PVDF) – during electrochemical lithiation and delithiation. During galvanostatic lithiation at very slow rates, the stress in a CMC-based electrode becomes compressive and increases to 70 MPa, where it reaches a plateau and increases slowly thereafter with capacity. The PVDF-based electrode exhibits similar behavior, although with lower peak compressive stress of about 12 MPa. These initial experiments indicate that the stress evolution in a Si composite electrode depends strongly on the mechanical properties of the binder. Stressmore » data obtained from a series of lithiation/delithiation cycles suggests plasticity induced irreversible shape changes in contacting Si particles, and as a result, the stress response of the system during any given lithiation/delithiation cycle depends on the cycling history of the electrode. While these results constitute the first in situ stress measurements on composite Si electrodes during electrochemical cycling, the diagnostic technique described herein can be used to assess the mechanical response of a composite electrode made with other active material/binder combinations.« less
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