Tough Gel Electrolyte Using Double Polymer Network Design for the Safe, Stable Cycling of Lithium Metal Anode

Abstract

With high capacity, lithium (Li) metal is considered to enable at least two-times the energy density for lithium batteries. The growth of lithium dendrite and low columbic efficiency restrict the development of Li metal anode. Solid polymer electrolytes are expected to be promising candidates to solve the issue. But how to get polymer electrolyte which integrates high ionic conductivity and high mechanical strength is still challenging. Here, by introducing a double polymer network chemistry into electrolyte design to reshape, we have successfully developed a tough polymer electrolyte with high conductivity and further realized the stable operation of lithium metal anodes. The DNW gel electrolyte has high modulus of 44.3 MPa and high fracture energy of 8.2 kJ m-2. By using this gel electrolyte design, we can realize a stable cycling of lithium metal electrode for more than 400 cycles with a columbic efficiency (CE) as high as 96.3% with carbonates based electrolytes.