Low-pressure Dendrite-free Sulfide Solid-state Battery with 3D LiSi@Li-Phen-Ether Anode

Lithium-metal batteries with solid electrolytes (SEs) have emerged as promising electrochemical energy storage devices due to high energy density and safety. However, inherent challenges of deleterious lithium dendrite growth and poor interfacial stability hinder their practical application. Herein, a new type of room-temperature liquidous Li metal arene complex—Li-Phenanthrene (Phen)-Ether is explored to enable a 3D LiSi@Li-Phen-Ether (3D LSLL) anode with low cost, high safety and high ion/electron-conductivity. Symmetric cells with sulfide SE and 3D LSLL anode deliver an ultra-high critical current density (> 13 mA cm−2) and long cycle life (> 1000 h, 0.25 mA cm−2). Moreover, full battery (LFP/sulfide SE/3D LSLL) can operate at low-external pressure (0.5 MPa) and ambient temperature by introducing a flexible cathode/sulfide interlayer with high ion conductivity (2 mS cm−1). This unprecedented battery configuration demonstrates high-rate (2C) performance and long cycle life (over 300 cycles), which exceeds preciously-reported sulfide SE/lithium batteries at low stack pressures, and may open up a promising route for high-energy-density, cost-effective and safe rechargeable lithium batteries.