A VISION OF THE FUTURE FOR SODIUM-ION BATTERIES

(Article published in Automotive Innovations magazine, August 2024)

By Marc Bardiaux

In Canada, almost all electric vehicles (EVs) are powered by LFP (lithium-iron-phosphate) batteries. But in the face of strong economic and environmental pressures, there was a need for alternative solutions. This is where sodium-ion batteries come in.

Sales of EVs are reaching unprecedented heights and, according to Atlas Magazine, there will be no fewer than ten million units worldwide by 2023. Forecasts suggest that by 2030, 50 % of the global vehicle fleet will be made up of EVs. Sodium-ion batteries therefore offer a promising alternative to lithium-iron-phosphate batteries. They are distinguished by their use of sodium, an abundant and inexpensive element which eliminates the need for critical materials such as cobalt, nickel and lithium. This is a crucial feature at a time when supply disruptions are looming as extraction becomes increasingly problematic.

Substantial Savings

Compared with LFPs, sodium-ion batteries could cut production costs by 20–30%, thanks to the abundance of sodium and its much more affordable extraction cost. In addition, the adoption of aluminum for the anode current collector, instead of the copper used in LFP batteries, promises further savings, while reducing the risk of supply chain disruptions.

Although sodium-ion batteries offer a lifespan of just a few hundred cycles at a higher weight than LFP batteries, significant progress is being made to improve their storage capacity, mass and longevity. Recent developments include the use of new materials for the anode and cathode, such as Prussian white, polyanion and stratified oxide.

Performance and Safety on the Menu

In terms of safety, sodium batteries are more resistant to extreme temperatures and less likely to catch fire than lithium batteries. Their electrolytes have a higher flash point, reducing risks during transport and disposal. What’s more, they can be fully discharged without danger, unlike lithium batteries, which require a minimum storage of at least 30 % for safety reasons. But it’s when it comes to recharging time that sodium batteries really stand out, as they only take a few minutes to reach full charge.

Although sodium-ion batteries still present technological challenges to be overcome, their potential suggests performance is far superior to that of LFP batteries currently in use. Their adoption could not only reduce the dependency on critical materials, but also help to stabilize supply and thus adequately meet the growing demand for EVs.

PICTURE CREDIT : StockCake (royalty-free photo)