# Quasi-Solid-State Na–O2 Battery with Composite Polymer Electrolyte

## TL;DR

This paper presents a quasi-solid-state Na–O2 battery using a composite polymer electrolyte to improve safety and performance.

## Contribution

A composite polymer electrolyte with PEO, NaTFSI, and NZSP is developed for enhanced ionic conductivity and safety in Na–O2 batteries.

## Key findings

- The composite polymer electrolyte achieved an ionic conductivity of 10–4 S cm–1 at room temperature.
- The electrolyte design provides superior resistance to dendritic penetration and reduces combustion risks.
- Nanosized NZSP enhances ion conduction pathways in the polymer matrix.

## Abstract

Na–O2 batteries have emerged as promising candidates
due to their high theoretical energy density (1,601 Wh kg–1), the potential for high energy storage efficiency, and the abundance
of sodium in the earth’s crust. Considering the safety issue,
quasi-solid-state composite polymer electrolytes are among the promising
solid-state electrolyte candidates. Their higher mechanical toughness
provides superior resistance to dendritic penetration compared with
traditional liquid electrolytes. The flexibility of the composite
polymer electrolyte matrix allows it to conform to various battery
configurations and considerably reduces safety concerns related to
the combustion risks associated with conventional liquid electrolytes.
In this study, we employed poly(ethylene oxide) (PEO) and sodium bis(trifluoromethanesulfonyl)imide
(NaTFSI) as the polymer matrix and sodium ion-conducting agent, respectively.
We incorporated nanosized NZSP (25 wt %) to create the composite polymer
electrolyte membrane. This CPE design facilitates ion conduction pathways
through both sodium salt and NZSP. By utilizing a liquid electrolyte
infiltration method, we successfully enhanced its ionic conductivity,
achieving an ionic conductivity of 10–4 S cm–1 at room temperature.