title: Lithium-assisted electrochemical welding in silicon nanowire battery electrodes.
abstract: From in situ transmission electron microscopy (TEM) observations, we present direct evidence of lithium-assisted welding between physically contacted silicon nanowires (SiNWs) induced by electrochemical lithiation and delithiation. This electrochemical weld between two SiNWs demonstrates facile transport of lithium ions and electrons across the interface. From our in situ observations, we estimate the shear strength of the welded region after delithiation to be approximately 200 MPa, indicating that a strong bond is formed at the junction of two SiNWs. This welding phenomenon could help address the issue of capacity fade in nanostructured silicon battery electrodes, which is typically caused by fracture and detachment of active materials from the current collector. The process could provide for more robust battery performance either through self-healing of fractured components that remain in contact or through the formation of a multiconnected network architecture.
authors.affiliation: Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: Khim
authors.initials: K
authors.lastname: Karki
authors.forename: Eric
authors.initials: E
authors.lastname: Epstein
authors.forename: Jeong-Hyun
authors.initials: JH
authors.lastname: Cho
authors.forename: Zheng
authors.initials: Z
authors.lastname: Jia
authors.forename: Teng
authors.initials: T
authors.lastname: Li
authors.forename: S Tom
authors.initials: ST
authors.lastname: Picraux
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Wang
authors.forename: John
authors.initials: J
authors.lastname: Cumings
mesh_terms: D011211:Electric Power Supplies; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008094:Lithium / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D014896:Welding / Q000295:instrumentation* / Q000379:methods
chemical_list: D008094:Lithium; D012825:Silicon