Bilayer Heterostructure Solid Electrolyte Developed by Donghua University

Recently, Professor  Qiuwei Shi and Professor Hongzhi Wang from Donghua University developed a bilayer heterostructure solid electrolyte, which can quickly form an electrochemically stable interface, which is helpful for the development of high energy density and high safety metal lithium batteries.

Solid-state electrolytes , usually composed of polymer matrix, lithium salt and inorganic ceramic electrolyte powder, has great potential in improving battery energy density, extending service life, and improving the safety performance of lithium ion batteries. In this study, a dual-composite concept is applied to the design of a bilayer heterostructure solid electrolyte composed of Li⁺ conductive garnet nanowires (Li_6.75La₃Zr_1.75Nb_0.25O₁₂)/polyvinylidene fluoride-co-hexafluoropropylene as a tough matrix and modified metal organic framework particles/polyethylene oxide/PVDF-HFP as an interfacial gel.

The integral ionic conductivity of the solid electrolyte reaches 2.0 x10⁻⁴Scm⁻¹ at room temperature. In addition, a chemically/electrochemically stable interface is rapidly formed, and Li dendrites are well restrained by a robust inorganic shield and matrix. As a result, steady Li plating/stripping for more than 1700 h at 0.25 mAcm⁻² is achieved.

The experimental results prove that solid‐state batteries using this bilayer heterostructure solid electrolyte deliver promising battery performance (efficient capacity output and cycling stability) at ambient temperature (25 °C). Not only that, solid-state batteries are using nails In a series of extreme environmental/conditional application tests such as hitting, burning, immersing in water and freezing in liquid nitrogen, it still shows considerable flexibility and excellent durability.

References: Jianqi Sun, et al, Facilitating Interfacial Stability Via Bilayer Heterostructure Solid Electrolyte Toward High-energy, Safe and Adaptable Lithium Batteries, Adv. Energy Mater. 2020, DOI: 10.1002/aenm.202000709