Numerical Solution of Moving Phase Boundary and Diffusion-Induced Stress of Sn Anode in the Lithium-Ion Battery

Journal Article · Wed Aug 02 00:00:00 EDT 2017 · Journal of the Electrochemical Society

DOI: https://doi.org/10.1149/2.0661711jes · OSTI ID:1425631

Chen, Chun-Hao ^[1]; Chason, Eric ^[2]; Guduru, Pradeep R. ^[2]

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1. Brown Univ., Providence, RI (United States). School of Engineering; Brown University, Providence, Rhode Island
2. Brown Univ., Providence, RI (United States). School of Engineering

Here, we have previously observed a large transient stress in Sn film anodes at the beginning of the Sn-Li₂Sn₅ phase transformation. To understand this behavior, we use numerical modeling to simulate the kinetics of the 1-D moving boundary and Li diffusion in the Sn anodes. A mixture of diffusion-controlled and interface-controlled kinetics is found. The Li concentration in the Li₂Sn₅ phase remains near a steady-state profile as the phase boundary propagates, whereas the Li diffusion in Sn is more complicated. Li continuously diffuses into the Sn layer and produces a supersaturation; the Li can then diffuse toward the Sn/Li₂Sn₅ interface and contribute to further phase transformation. Finally, the evolution of Li concentration in the Sn induces strain which involves rate-dependent plasticity and elastic unloading, resulting in the complex stress evolution that is observed. In the long term, the measured stress is dominated by the stress in the growing Li₂Sn₅ phase.

• Research Organization: Brown Univ., Providence, RI (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0007074
• OSTI ID: 1425631
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 11 Vol. 164; ISSN 0013-4651
• Publisher: The Electrochemical SocietyCopyright Statement
• Country of Publication: United States
• Language: English