Gao Yue, Wang Daiwei, Shin Yun Kyung, Yan Zhifei, Han Zhuo, Wang Ke, Hossain Md Jamil, Shen Shuling, AlZahrani Atif, van Duin Adri C T, Mallouk Thomas E, Wang Donghai
Department of Mechanical Engineering, The Pennsylvania State University, University Park, PA 16802.
Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104.
Proc Natl Acad Sci U S A. 2020 Dec 1;117(48):30135-30141. doi: 10.1073/pnas.2001837117. Epub 2020 Nov 16.
Metallic anodes (lithium, sodium, and zinc) are attractive for rechargeable battery technologies but are plagued by an unfavorable metal-electrolyte interface that leads to nonuniform metal deposition and an unstable solid-electrolyte interphase (SEI). Here we report the use of electrochemically labile molecules to regulate the electrochemical interface and guide even lithium deposition and a stable SEI. The molecule, benzenesulfonyl fluoride, was bonded to the surface of a reduced graphene oxide aerogel. During metal deposition, this labile molecule not only generates a metal-coordinating benzenesulfonate anion that guides homogeneous metal deposition but also contributes lithium fluoride to the SEI to improve Li surface passivation. Consequently, high-efficiency lithium deposition with a low nucleation overpotential was achieved at a high current density of 6.0 mA cm A Li|LiCoO cell had a capacity retention of 85.3% after 400 cycles, and the cell also tolerated low-temperature (-10 °C) operation without additional capacity fading. This strategy was applied to sodium and zinc anodes as well.
金属阳极(锂、钠和锌)对于可充电电池技术具有吸引力,但却受到不利的金属-电解质界面的困扰,这种界面会导致金属沉积不均匀以及固体电解质界面(SEI)不稳定。在此,我们报告了使用电化学不稳定分子来调节电化学界面,并引导均匀的锂沉积和稳定的SEI。该分子苯磺酰氟被键合到还原氧化石墨烯气凝胶的表面。在金属沉积过程中,这种不稳定分子不仅会生成引导均匀金属沉积的金属配位苯磺酸根阴离子,还会为SEI贡献氟化锂以改善锂表面的钝化。因此,在6.0 mA cm的高电流密度下实现了具有低成核过电位的高效锂沉积。一个Li|LiCoO电池在400次循环后容量保持率为85.3%,并且该电池还能耐受低温(-10°C)运行而不会出现额外的容量衰减。这种策略也应用于钠和锌阳极。