All-solid-state lithium–sulfur batteries enabled by single-ion conducting binary nanoparticle electrolytes

Abstract

We designed solid-state hybrid electrolytes with single-ion conducting properties by co-assembling binary core–shell polymer nanoparticles. By controlling the nanoparticle size and number, we created superlattices that optimized the Li⁺ concentration and transport. The electrolytes exhibited a remarkable ionic conductivity (10⁻⁴ S cm⁻¹), lithium transference number (0.94), electrochemical stability (up to 6 V), and modulus (0.12 GPa) at 25 °C. The mechanical strength of these electrolytes depended minimally on temperature at 25–150 °C because of the robustness of the cores. When implemented in Li–S batteries with no liquids, they demonstrated an initial discharge capacity of 1090 mA h g⁻¹ at 0.05C, a cycle life of over 200 cycles, and a rate capability with a discharge capacity of 627 mA h g⁻¹ at 3C.