title: Self-healing chemistry enables the stable operation of silicon microparticle anodes for high-energy lithium-ion batteries.
abstract: The ability to repair damage spontaneously, which is termed self-healing, is an important survival feature in nature because it increases the lifetime of most living creatures. This feature is highly desirable for rechargeable batteries because the lifetime of high-capacity electrodes, such as silicon anodes, is shortened by mechanical fractures generated during the cycling process. Here, inspired by nature, we apply self-healing chemistry to silicon microparticle (SiMP) anodes to overcome their short cycle-life. We show that anodes made from low-cost SiMPs (~3-8 µm), for which stable deep galvanostatic cycling was previously impossible, can now have an excellent cycle life when coated with a self-healing polymer. We attain a cycle life ten times longer than state-of-art anodes made from SiMPs and still retain a high capacity (up to ~3,000 mA h g(-1)). Cracks and damage in the coating during cycling can be healed spontaneously by the randomly branched hydrogen-bonding polymer used.
authors.affiliation: 1] Department of Chemical Engineering, Stanford University, California 94305, USA [2].
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Chen
authors.forename: Matthew T
authors.initials: MT
authors.lastname: McDowell
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui
authors.forename: Zhenan
authors.initials: Z
authors.lastname: Bao