title: Ambient-Air Stable Lithiated Anode for Rechargeable Li-Ion Batteries with High Energy Density.
abstract: An important requirement of battery anodes is the processing step involving the formation of the solid electrolyte interphase (SEI) in the initial cycle, which consumes a significant portion of active lithium ions. This step is more critical in nanostructured anodes with high specific capacity, such as Si and Sn, due to their high surface area and large volume change. Prelithiation presents a viable approach to address such loss. However, the stability of prelithiation reagents is a big issue due to their low potential and high chemical reactivity toward O2and moisture. Very limited amount of prelithiation agents survive in ambient air. In this research, we describe the development of a trilayer structure of active material/polymer/lithium anode, which is stable in ambient air (10-30% relative humidity) for a period that is sufficient to manufacture anode materials. The polymer layer protects lithium against O2and moisture, and it is stable in coating active materials. The polymer layer is gradually dissolved in the battery electrolyte, and active materials contact with lithium to form lithiated anode. This trilayer-structure not only renders electrodes stable in ambient air but also leads to uniform lithiation. Moreover, the degree of prelithiation could vary from compensating SEI to fully lithiated anode. With this strategy, we have achieved high initial Coulombic efficiency of 99.7% in graphite anodes, and over 100% in silicon nanoparticles anodes. The cycling performance of lithiated anodes is comparable or better than those not lithiated. We also demonstrate a Li4Ti5O12/lithiated graphite cell with stable cycling performance. The trilayer structure represents a new prelithiation method to enhance performance of Li-ion batteries.
authors.affiliation: Program of Materials Science and Engineering, Department of Applied Physics and Applied Mathematics, Columbia University , New York 10027, New York.
authors.forename: Zeyuan
authors.initials: Z
authors.lastname: Cao
authors.affiliation: Program of Materials Science and Engineering, Department of Applied Physics and Applied Mathematics, Columbia University , New York 10027, New York.
authors.forename: Pengyu
authors.initials: P
authors.lastname: Xu
authors.affiliation: Program of Materials Science and Engineering, Department of Applied Physics and Applied Mathematics, Columbia University , New York 10027, New York.
authors.forename: Haowei
authors.initials: H
authors.lastname: Zhai
authors.affiliation: Program of Materials Science and Engineering, Department of Applied Physics and Applied Mathematics, Columbia University , New York 10027, New York.
authors.forename: Sicen
authors.initials: S
authors.lastname: Du
authors.affiliation: Program of Materials Science and Engineering, Department of Applied Physics and Applied Mathematics, Columbia University , New York 10027, New York.
authors.forename: Jyotirmoy
authors.initials: J
authors.lastname: Mandal
authors.affiliation: IREQ-Institute Recherche d'Hydro-Québec , 1800 Boulevard Lionel Boulet, Varennes, Quebec J3X 1S1, Canada.
authors.forename: Martin
authors.initials: M
authors.lastname: Dontigny
authors.affiliation: IREQ-Institute Recherche d'Hydro-Québec , 1800 Boulevard Lionel Boulet, Varennes, Quebec J3X 1S1, Canada.
authors.forename: Karim
authors.initials: K
authors.lastname: Zaghib
authors.affiliation: Program of Materials Science and Engineering, Department of Applied Physics and Applied Mathematics, Columbia University , New York 10027, New York.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yang
keywords: Coulombic efficiency; PMMA; energy storage; prelithiation; silicon anode; solid electrolyte interphase