Dendrite-free lithium-metal all-solid-state batteries by solid-phase passivation

All-solid-state battery (ASSB) with Li metal anode is the most promising energy-storage technology with higher energy and power densities. However, the interfacial reaction at Li/solid electrolyte (SE) interface and Li dendrite penetration into SE will result in low coulombic efficiency (CE), short circuit, safety hazard and poor cycle life of lithium-metal ASSBs. Herein, an effective solid-phase passivation (SPP) approach is proposed to overcome the above challenges by constructing an artificial solid electrolyte interphase (SEI) for interfacial protection. Driven by hot pressing, the passivator molecules of CuF2-PVDF-HFP reacts in-situ with lithium atoms to form a LiF/Cu multifunctional inorganic interlayer. The consequent symmetric cells with passivated artificial SEI demonstrates a remarkably high critical current density up to 3.7 mA cm-2 at room temperature and remains stable over 1000 h at a current density of 0.5 mA cm-2. LiCoO2/Li6PS5Cl/Li delivers a long-term cycling per-formance, where the capacity retains 82.19 % of its initial state after 300 cycles at 1 C/1.0 mA cm-2.

Automated summary

By constructing an artificial solid electrolyte interphase (SEI), the performance of all-solid-state lithium metal batteries can be improved while overcoming the issues of interfacial reactions and dendrite penetration. The passivated artificial SEI shows high current density and cycling performance.