Aging Processes in Lithiated FeSn2 Based Negative Electrode for Li-Ion Batteries: A New Challenge for Tin Based Intermetallic Materials

作者：Chamas, Mohamad; Mahmoud, Abdelfattah; Tang, Junlei; Sougrati, Moulay Tahar; Panero, Stefania; Lippens, Pierre-Emmanuel^*

来源：Journal of Physical Chemistry C, 2017, 121(1): 217-224.

DOI：10.1021/acs.jpcc.6b11302

• ALLOYED SN-FE(-C) POWDERS
• ANODE MATERIALS
• ELECTROCHEMICAL IMPEDANCE
• MOSSBAUER-SPECTROSCOPY
• LITHIUM
• NANOCOMPOSITE
• MECHANISMS
• INTERFACE
• SCALE

Tin-based intermetallic compounds proposed. as negative electrode materials for Li-ion batteries not only suffer from capacity fade,during cycling due to volume variations but also from aging phenomena in lithiated states. By using FeSn2 as a model compound; we propose an analysis of this process by combining electrochemical potential measurements, Sn-119 and Fe-57 Mossbauer spectroscopies, magnetic measurements, and impedance spectroscopy: We show that the Fe/Li7Sn2 composite obtained at the end of the first discharge is progressively transformed during the aging process occurring within the electrochemical open circuit condition. The Fe nano- particles are stable while the Li7Sn2 nanoparticles are progressively delithiated with time leading to Sn-rich Li Sn nanoalloys without observable back reaction with Fe. The deinserted lithium atoms react interphase-(SEI)- by increasing its thickness and/or decreasing its porosity.

• 出版日期2017-1-12
• 单位西南石油大学