Sweden’s Northvolt hails sodium battery breakthrough

NORTHVOLT says it has made a breakthrough in the development of sodium-ion batteries that could help reduce dependence on China.

The Swedish manufacturer says its new batteries can be made using locally sourced abundant materials including sodium and iron, and without critical metals. This means it can sever supply links with China which produces much of the world’s critical minerals needed for green energy technologies. China is also home to most of the 30 or so sodium-ion battery manufacturing plants that are operating, planned or under construction with a combined capacity of more than 100 GWh, according to figures from the IEA.

Peter Carlsson, CEO of Northvolt, said: “The world has put high hopes on sodium-ion, and I’m very pleased to say that we’ve developed a technology that will enable its widespread deployment to accelerate the energy transition. It’s an important milestone for Northvolt’s market proposition, but battery technology like this is also crucial to reach global sustainability goals, by making electrification more cost-efficient, sustainable, and accessible worldwide.”

Northvolt says the battery has been validated with an energy density of 160 Wh/kg, the high end of the range achieved for sodium-ion batteries. It says the technology will primarily suit energy storage applications and it plans to develop future generations that will suit use in electric vehicles.

It expects that the operating safety of its new battery at high temperatures should make it an attractive option for energy storage projects in growing markets in India, the Middle East and Africa. The battery, whose cathode is made from Prussian white with a hard carbon-based anode, will provide the foundation for its next generation of energy storage technology. Customers for its existing lithium-ion battery products include carmakers Volvo, Volkswagen, and BMW.

While sodium-ion batteries are touted as safer and less sensitive to temperature changes, the trade-off is that they are less energy dense than their lithium-ion counterparts, which range from 120-260 Wh/kg. Despite this, carmakers are starting to transition to sodium-ion batteries with Chinese carmaker BYD, the world’s second-largest producer of electric vehicles, committing this year to build a dedicated battery manufacturing plant for small cars.

Lithium-ion pioneer John Goodenough, who was awarded the 2019 Nobel Prize in chemistry for his research into the technology during the 1980s, went on to publish studies in the 2010s on the potential of sodium-ion cathode materials using the materials Prussian blue and Prussian white. His 2015 study inspired the research of master’s student Ronnie Mogensen who went on to form battery research firm Altris which has partnered with Northvolt on the development of the new battery.