Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742, USA.
Maryland Energy Innovation Institute, University of Maryland, College Park, MD, 20742, USA.
Adv Mater. 2018 Nov;30(48):e1802068. doi: 10.1002/adma.201802068. Epub 2018 Oct 9.
Lithium-metal batteries are considered one of the most promising energy-storage systems owing to their high energy density, but their practical applications have long been hindered by significant safety concerns and poor cycle stability. Solid-state electrolytes (SSEs) are expected to improve not only the safety but also the energy density of Li-metal batteries. The key challenge for solid-state Li-metal batteries lies in the low ionic conductivity of the SSEs and moreover the interface contact between the electrode and SSE. To achieve feasible solid-state Li-metal batteries, it is imperative that the ionic conductivity is improved, especially at the electrode-SSE interface. Herein, recent advances in interface engineering for solid-state Li-metal batteries are reported, mainly focusing on garnet-type SSEs. Various materials to modify the cathode-garnet and Li-garnet interfaces by intermediate layers, alloys, and polymer electrolytes are analyzed. Structural innovations for SSEs including composite electrolytes and multilayer SSE frameworks are reviewed, along with advanced characterization approaches to probe the interfaces, which will provide further insights for garnet-based solid-state batteries. Future challenges and the great promise of garnet-based Li-metal batteries are discussed to close.
锂金属电池因其高能量密度而被认为是最有前途的储能系统之一，但由于存在重大安全问题和较差的循环稳定性，其实际应用长期受到阻碍。固态电解质（SSE）有望提高锂金属电池的安全性和能量密度。固态锂金属电池的关键挑战在于 SSE 的离子电导率低，而且电极与 SSE 之间的界面接触不良。为了实现可行的固态锂金属电池，必须提高离子电导率，特别是在电极-SSE 界面处。本文主要针对石榴石型 SSE 报道了固态锂金属电池界面工程的最新进展。通过中间层、合金和聚合物电解质来修饰正极-石榴石和 Li-石榴石界面的各种材料进行了分析。对包括复合电解质和多层 SSE 框架在内的 SSE 结构创新进行了综述，以及用于探测界面的先进表征方法，这将为基于石榴石的固态电池提供进一步的见解。最后讨论了基于石榴石的锂金属电池面临的未来挑战和巨大前景。
