Highly rough copper current collector: improving adhesion property between a silicon electrode and current collector for flexible lithium-ion batteries. Issue 57 (19th July 2017)

• Record Type: Journal Article
• Authors: Jeon, Hyunkyu; Cho, Inseong; Jo, Hearin; Kim, Kyuman; Ryou, Myung-Hyun; Lee, Yong Min
• Is Part Of: RSC advances. Volume 7:Issue 57(2017)
• Page Start: 35681
• Page End: 35686
• Publication Date: 2017-07-19
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7ra04598k
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Rough Cu foil enhances the adhesion properties between Si electrode composites and Cu foil due to physical interlocking. Abstract : Two types of Cu foil, conventional flat Cu foil and rough Cu foil, are used to fabricate silicon (Si) electrodes for flexible and high-energy-density lithium-ion batteries (LIBs). Confocal microscopy and cross-sectional SEM images reveal the roughness of the very rough Cu foil to be approximately 3 μm, whereas the conventional flat Cu foil has a smooth surface and a roughness of less than 1 μm. This difference leads to the improvement of the interfacial adhesion strength between the Si electrode and the Cu foil from 89.7 (flat Cu foil) to 135.7 N m −1 (rough Cu foil), which is measured by a versatile peel tester. As a result, the Si electrode with high Si content (80 wt%) can deliver a significantly higher discharge capacity of 1500 mA h g −1 after 200 cycles, even at a current rate of 1200 mA g −1 . Furthermore, when the corresponding Si electrode is assembled into a pouch-type cell and cycled in the rolled conformation with a radius of 6.5 mm, the Si electrode with rough Cu foil shows a stable cycle performance due to better interfacial adhesion.