High-performance lithium metal batteries with ultraconformal interfacial contacts of quasi-solid electrolyte to electrodes

We report an in-situ strategy initiating polymerization of liquid electrolytes in electrochemical cells to produce quasi-solid electrolytes with cross-linked structure; with such a strategy, ultraconformal interfacial contacts between cathode/electrolyte and electrolyte/anode are created. The solid electrolyte exhibits a high ionic conductivity of 4.3 mS cm(-1), a Li-ion transference number of 0.55 at room temperature and a wide electrochemical window of 5.2 V. The robust LiF-rich solid electrolyte interphase (SEI) layer on the Li anode effectively prevents the dendrite growth and the pulverization of the Li anode. By applying the quasi-solid electrolyte in Li-LiNi0.85Co0.05Al0.1O2 (NCA), Li-LiNi0.6Co0.2Mn0.2O2 (NCM622) batteries, high specific discharge capacities and long cycling lifetime are achieved at large current densities. This work demonstrates the tremendous potential of the in-situ strategy in promoting the application of high-voltage Li metal batteries.