title: Artificial Solid Electrolyte Interphase-Protected LixSi Nanoparticles: An Efficient and Stable Prelithiation Reagent for Lithium-Ion Batteries.
abstract: Prelithiation is an important strategy to compensate for lithium loss in lithium-ion batteries, particularly during the formation of the solid electrolyte interphase (SEI) from reduced electrolytes in the first charging cycle. We recently demonstrated that LixSi nanoparticles (NPs) synthesized by thermal alloying can serve as a high-capacity prelithiation reagent, although their chemical stability in the battery processing environment remained to be improved. Here we successfully developed a surface modification method to enhance the stability of LixSi NPs by exploiting the reduction of 1-fluorodecane on the LixSi surface to form a continuous and dense coating through a reaction process similar to SEI formation. The coating, consisting of LiF and lithium alkyl carbonate with long hydrophobic carbon chains, serves as an effective passivation layer in the ambient environment. Remarkably, artificial-SEI-protected LixSi NPs show a high prelithiation capacity of 2100 mA h g(-1) with negligible capacity decay in dry air after 5 days and maintain a high capacity of 1600 mA h g(-1) in humid air (∼10% relative humidity). Silicon, tin, and graphite were successfully prelithiated with these NPs to eliminate the irreversible first-cycle capacity loss. The use of prelithiation reagents offers a new approach to realize next-generation high-energy-density lithium-ion batteries.
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhao
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Zhenda
authors.initials: Z
authors.lastname: Lu
authors.affiliation: ‡Department of Applied Physics, Stanford University, Stanford, California 94305, United States.
authors.forename: Haotian
authors.initials: H
authors.lastname: Wang
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Hyun-Wook
authors.initials: HW
authors.lastname: Lee
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Kai
authors.initials: K
authors.lastname: Yan
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Denys
authors.initials: D
authors.lastname: Zhuo
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
authors.forename: Dingchang
authors.initials: D
authors.lastname: Lin
authors.affiliation: §Department of Chemistry, Stanford University, Stanford, California 94305, United States.
authors.forename: Nian
authors.initials: N
authors.lastname: Liu
authors.affiliation: †Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.|∥Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States.
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui