The fireproof future of energy storage

The innovative salt battery, originally developed for electric cars, is now a safe solution for supplying energy to critical infrastructures such as mobile phone antennas. Thanks to its longevity and safety, it is considered a pioneering solution - with the potential to one day supply entire neighbourhoods with electricity.

The salt battery, an integral part of early electromobility, is a safe and durable storage medium that is convincing in various applications. In contrast to lithium-ion batteries, the salt battery uses a solid, ceramic electrolyte that is neither flammable nor explosive. In Switzerland, Empa researchers are working with industrial partners to further improve the performance and efficiency of this technology.

Advantages over conventional batteries
The solid-state architecture and high operating temperature of around 300°C make the salt battery particularly suitable for extreme applications such as tunnelling or offshore installations, where safety is a top priority. Due to its temperature resistance and low-maintenance design, it is also used for the emergency power supply of mobile phone antennas, which have to work reliably for decades even under harsh conditions.

Economic efficiency and challenges
One disadvantage of the salt battery is its high operating temperature, which requires a basic consumption of energy. Empa researchers such as Meike Heinz and Enea Svaluto-Ferro are therefore working on cell structures that enable the battery to heat itself during use and thus work more efficiently. Despite the additional energy requirement, the salt battery is considered more economical and stable than many alternatives in certain applications.

Resource-saving raw materials and recycling systems
Another advantage is the availability of the required raw materials: Sodium and aluminium are inexpensive and plentiful, making battery production cost-effective and sustainable. Empa’s current research focus is on reducing the nickel content in the cells in order to further reduce the ecological footprint. In future projects, zinc could even replace nickel – an option that could further improve access to sustainable energy storage systems.

Future prospects
As research progresses, the salt battery could find its way from specialised fields of application to broad, stationary applications. Its use as a long-lasting and safe storage system for residential areas or neighbourhoods is being seriously considered. It thus offers an innovative alternative to lithium-ion batteries and shows how research at Empa can set the course for the future of energy storage.

Quelle: EMPA