Accelerated short circuiting in anode‐free solid‐state batteries driven by local lithium depletion
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
“Anode-free” solid-state batteries (SSBs), which have no anode active material, can exhibit extremely high energy density (≈1500 Wh L−1). However, there is a lack of understanding of the lithium plating/stripping mechanisms at initially lithium-free solid-state electrolyte (SSE) interfaces because excess lithium metal is often used. Here, it is demonstrated that commercially relevant quantities of lithium (>5 mAh cm−2) can be reliably plated at moderate current densities (1 mA cm−2) using the sulfide SSE Li6PS5Cl. Investigations of lithium plating/stripping mechanisms, in conjunction with cryo-focused ion beam (FIB) imaging, synchrotron tomography, and phase-field modeling, reveal that the cycling stability of these cells is fundamentally limited by the nonuniform presence of lithium during stripping. Local lithium depletion causes isolated lithium regions toward the end of stripping, decreasing electrochemically active area and resulting in high local current densities and void formation. This accelerates subsequent filament growth and short circuiting compared to lithium-excess cells. Despite this degradation mode, it is shown that anode-free cells exhibit comparable Coulombic efficiency to lithium-excess cells, and improved resistance to short circuiting is achieved by avoiding local lithium depletion through retention of thicker lithium at the interface. These new insights provide a foundation for engineering future high-energy anode-free SSBs.
Date Issued
2023-03-24
Date Acceptance
2023-02-01
Citation
Advanced Energy Materials, 2023, 13 (12), pp.1-12
ISSN
1614-6832
Publisher
Wiley
Start Page
1
End Page
12
Journal / Book Title
Advanced Energy Materials
Volume
13
Issue
12
Copyright Statement
© 2023 Wiley-VCH GmbH. This is the peer reviewed version of the following article, which has been published in final form at https://onlinelibrary.wiley.com/doi/10.1002/aenm.202204186. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.
Identifier
http://dx.doi.org/10.1002/aenm.202204186
Publication Status
Published
Date Publish Online
2023-02-12