Architected Macroporous Polyelectrolytes That Suppress Dendrite Formation during High-Rate Lithium Metal Electrodeposition

Abstract

Batteries assembled with lithium metal anodes and high-capacity cathodes—including air, sulfur, and lithium-rich transition metal oxides—have higher energy density than conventional Li-ion counterparts. Unfortunately, the lifetime of lithium metal cells is typically short, owing to the formation of dendrites on charging, which eventually shorts the cells. Short cycle life is also observed when lithium deposits with a “mossy” morphology; the high surface area of mossy deposits increases the rate of electrolyte degradation, eventually drying out the cells. Here we show that a lithium-ion-conducting, architected macroporous polyelectrolyte (AMP-1) serves as a long-lasting host for uniform and dense lithium–metal electrodeposits. High Coulombic efficiencies indicate the low occurrence of parasitic reactions with the electrolyte. Galvanostatic discharge experiments indicate that AMP-1 suppresses dendrite formation, extending over 2-fold the short-circuit time at high current density. Our success opens new dire...