Three-Dimensional Porous Copper-Tin Alloy Electrodes for Rechargeable Lithium Batteries

• Published in: Advanced functional materials Vol. 15; no. 4; pp. 582 - 586
• Main Authors: Shin, H.-C., Liu, M.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01-04-2005; WILEY‐VCH Verlag
• Subjects: Alloys; Alloys, copper–tin; Composite materials; Composite materials, metals; copper-tin; Electrodeposition; Lithium-ion batteries; metals; Porous materials
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.200305165

Three‐dimensional (3D) foam structure of a Cu6Sn5 alloy was fabricated via an electrochemical deposition process. The walls of the foam structure are highly porous and consist of numerous small grains. When used as a negative electrode for a rechargeable lithium battery, the Cu6Sn5 samples delivered a reversible capacity of about 400 mA h g–1 up to 30 cycles. Further, these materials exhibit superior rate capability, attributed primarily to the unique porous structure and the large surface area for fast mass transport and rapid surface reactions. For instance, at a current drain of 10 mA cm–2 (20C rate), the obtainable capacity (220 mA h g–1) was more than 50 % of the capacity at 0.5 mA cm–2 (1C rate).
Cu6Sn5 negative electrodes with a unique 3D foam structure are fabricated using an electrochemical deposition process. The highly porous walls of the foam structure consist of numerous small grains. At an extremely high cycling rate of 20 C, the obtainable capacity was about 50 % of that at 1 C rate (see Figure).