Si–Cu/carbon composites with a core–shell structure for Li-ion secondary battery

• Published in: Carbon (New York) Vol. 45; no. 10; pp. 1928 - 1933
• Main Authors: Kang, Yong-Mook, Park, Min-Sik, Lee, Jai-Young, Liu, Hua-Kun
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.09.2007; Elsevier Science
• Subjects: Chemistry; Colloidal state and disperse state; Cross-disciplinary physics: materials science; rheology; Electrochemistry; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; General and physical chemistry; Materials science; Physics; Porous materials; Specific materials; Degradation; Composite materials; Pore; Porous materials; Electrochemistry; Insertion; Ions; Extraction; Kinetics; Structure; Carbon; Particles
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2007.06.016

Si–Cu/carbon composites with a carbon core and a Si–Cu composite shell have been synthesized by two-step mechanical fusion process. Large amount of pores around composite particles as well as the bridging disordered carbon layer between Si–Cu composite and carbon was the structural advantage of Si–Cu/carbon composite, which could prevent the electrochemical degradation induced by enormous volume changes during Li + insertion or extraction. With these structural characteristics, the cyclic property of Si–Cu/carbon composite was greatly improved compared to Si. A phase-controlled shell (Si–Cu composite) acted as another advantage for this Si–Cu/carbon composite, as it rendered not only good ductility for accommodating the volume expansion, but also enhanced kinetics.