PNNL

Abstract

Rechargeable lithium (Li) metal batteries (LMBs) offer a great opportunity for applications needing high-energy-density battery systems. However, rare progress has been demonstrated so far under practical conditions including high voltage, high loading cathode, thin Li anode, and lean electrolyte. Here, in opposite to the common wisdom, we report an ether-based localized high concentration electrolyte that can greatly enhance the stability of Ni-rich LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode under 4.4 V and 4.5 V with an effective protection interphase enriched in LiF. This effect, in combination with the superior Li stability in this electrolyte, enables dramatically improved cycling performances of Li||NMC811 batteries under highly challenging conditions. The LMBs can retain over 80% capacity in 150 stable cycles with extremely limited amounts of Li anode and electrolyte. The findings in this work point out a very promising strategy to develop practical high-energy LMBs.