title: Effective Suppression of Dendritic Lithium Growth Using an Ultrathin Coating of Nitrogen and Sulfur Codoped Graphene Nanosheets on Polymer Separator for Lithium Metal Batteries.
abstract: The enhanced stability of lithium metal is vital to the development of high energy density lithium batteries due to its higher specific capacity and low redox potential. Herein, we demonstrate that nitrogen and sulfur codoped graphene (NSG) nanosheets coated on a polyethylene separator stabilized the lithium electrode in lithium metal batteries by effectively suppressing dendrite growth and maintaining a uniform ionic flux on the metal surface. The ultrathin layer of NSG nanosheets also improved the dimensional stability of the polymer separator at elevated temperatures. In addition, the enhanced interfacial interaction between the NSG-coated separator and lithium metal via electrostatic attraction released the surface tension of lithium metal and suppressed the initiation of dendrite growth on lithium metal. As a result, the electrochemical performance of a lithium metal cell composed of a LiNi0.8Co0.15Al0.05O2 positive electrode with an NSG-coated separator was remarkably improved as compared to the cell with an uncoated polyethylene separator.
authors.affiliation: Department of Chemical Engineering, Hanyang University , Seoul 133-791, Korea.
authors.forename: Won-Kyung
authors.initials: WK
authors.lastname: Shin
authors.affiliation: Department of Chemical Engineering, Hanyang University , Seoul 133-791, Korea.
authors.forename: Aravindaraj G
authors.initials: AG
authors.lastname: Kannan
authors.affiliation: Department of Chemical Engineering, Hanyang University , Seoul 133-791, Korea.
authors.forename: Dong-Won
authors.initials: DW
authors.lastname: Kim
keywords: coated separator; doped graphene; lithium dendrite; lithium metal battery; ultrathin coating