Rechargeable room-temperature (RT) sodium–sulfur (Na–S) batteries hold great potential for large-scale energy storage owing to their high energy density and low cost. However, their practical application is hindered by challenges such as polysulfide shuttling and Na dendrite formation. In this study, a dual salt-based quasi-solid polymer electrolyte (DS–QSPE) was developed via in situ polymerization, achieving high ionic conductivity (4.8 × 10⁻⁴ S·cm⁻¹ at 25 °C), a high sodium-ion transference number (0.73), and effective polysulfide confinement. Theoretical calculations and experimental results indicate that the enhanced Na-ion transport is attributed to the strengthened coordination of anions with the polydioxolane chain and the increased dissociation of sodium salts. Importantly, the DS–QSPE forms an interconnected network structure in the sulfurized polyacrylonitrile (SPAN) cathode. This provides abundant and seamless electrochemical reaction interfaces that facilitate efficient and uniform ion transport pathways. As a result, the Na||SPAN battery with DS–QSPE delivers a high capacity of approximately 327.4 mAh·g⁻¹ (based on the mass of SPAN) after 200 cycles at 0.2 A·g⁻¹, retaining 81.4% of its initial capacity. This performance considerably surpasses that of batteries using liquid electrolytes. This study offers a straightforward approach to addressing the interfacial challenges in solid-state Na–S batteries.

Symmetrical solid oxide cells (SSOCs) are very useful for energy generation and conversion. To fabricate the electrode of SSOC, it is very time-consuming to use the conventional approach. In this work, we design and develop a novel method, extreme heat treatment (EHT), to rapidly fabricate electrodes for SSOC. We show that by using the EHT method, the electrode can be fabricated in seconds (the fastest method to date), benefiting from enhanced reaction kinetics. The EHT-fabricated electrode presents a porous structure and good adhesion with the electrolyte. In contrast, tens of hours are needed to prepare the electrode by the conventional approach, and the prepared electrode exhibits a dense structure with a larger particle size due to the lengthy treatment. The EHT-fabricated electrode shows desirable electrochemical performance. Moreover, we show that the electrocatalytic activity of the perovskite electrode can be tuned by the vigorous approach of fast exsolution, deriving from the increased active sites for enhancing the electrochemical reactions. At 900 ℃, a promising peak power density of 966 mW cm⁻² is reached. Our work exploits a new territory to fabricate and develop advanced electrodes for SSOCs in a rapid and high-throughput manner.