title: Improving battery safety by early detection of internal shorting with a bifunctional separator.
abstract: Lithium-based rechargeable batteries have been widely used in portable electronics and show great promise for emerging applications in transportation and wind-solar-grid energy storage, although their safety remains a practical concern. Failures in the form of fire and explosion can be initiated by internal short circuits associated with lithium dendrite formation during cycling. Here we report a new strategy for improving safety by designing a smart battery that allows internal battery health to be monitored in situ. Specifically, we achieve early detection of lithium dendrites inside batteries through a bifunctional separator, which offers a third sensing terminal in addition to the cathode and anode. The sensing terminal provides unique signals in the form of a pronounced voltage change, indicating imminent penetration of dendrites through the separator. This detection mechanism is highly sensitive, accurate and activated well in advance of shorting and can be applied to many types of batteries for improved safety.
authors.affiliation: 1] Department of Materials Science and Engineering, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA [2] State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Materials Science and Engineering, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA.
authors.forename: Denys
authors.initials: D
authors.lastname: Zhuo
authors.affiliation: Department of Materials Science and Engineering, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA.
authors.forename: Desheng
authors.initials: D
authors.lastname: Kong
authors.affiliation: 1] Department of Materials Science and Engineering, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA [2] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui