 Abstract seawater battery, SWB, technology has been gaining traction due to its low cost, abundant materials, and potential for long-term energy storage. However, the poor interface between the solid electrolyte and the anode has limited the development of SWBs. This study introduces titanium dioxide, TiO2, doped sodium zirconium silicate, Na3ZR2C2PO12, NZSP, membranes to improve the interface between the anode and the solid electrolyte. The resulting dense, porous structure of the TiO2, doped NZSP membrane improves ionic conductivity and increases the capacity of the battery. Additionally, stable cycling performance with reversible capacities based on different Na storage mechanisms were demonstrated. This article was authored by Minyali, Marm Dixit, Rashid Essaly, and others.