Our guest for today's show is Prof. Stefano Passerini. As battery researcher he works for the Austrian Institute of Technology (AIT) in Vienna, he is the former director of the Helmholtz Institute Ulm (HIU) and Senior Distinguished Fellow of the Karlsruhe Institute of Technology (KIT).

Sodium-ion batteries (SIBs) are emerging as a promising alternative to lithium-ion batteries, primarily due to the abundance and affordability of sodium compared to lithium. Recent research has focused on enhancing their performance to make them viable for various applications, including stationary battery container parks and light electric vehicles.​

Researchers have made significant strides in developing novel cathode and anode materials to improve the energy density and lifespan of SIBs. Innovations include the use of layered transition metal oxides and hard carbon anodes, which have shown improved capacity and stability. Additionally, advancements in electrolyte formulations have contributed to enhanced conductivity and battery longevity. ​

For Europe, Sodium-ion technology is gaining strategic importance, especially in the context of reducing reliance on lithium, which is predominantly sourced from regions with geopolitical constraints. European battery researchers are investing in the development of SIBs to enhance energy security and reduce dependence on lithium imports. Sodium's abundance within Europe is seen as a potential game-changer for domestic battery production. ​

While SIBs currently offer lower energy density compared to lithium-ion batteries, ongoing research aims to bridge this gap. Researcher's forecast suggests that sodium-ion batteries could capture about 10% of annual global energy storage additions by 2030, particularly in applications where cost-effectiveness and the use of locally sourced materials are prioritized. ​

A seawater sodium-ion (Na) battery is an energy storage device that uses seawater as a key electrolyte, utilizing the abundant sodium ions found in seawater instead of the more expensive and scarce lithium. The battery operates by extracting sodium ions from the seawater during charging and storing them in the anode. During discharge, the ions return to the cathode, releasing energy. Seawater Na batteries are considered environmentally friendly and cost-effective due to the abundance of sodium. However, challenges like improving energy density and longevity remain, with ongoing research aiming to enhance their performance for large-scale energy storage.