China’s first sodium-ion battery energy storage station could cut reliance on lithium

“The energy conversion efficiency of this sodium-ion battery energy storage system is over 92 per cent, higher than the current common lithium-ion battery energy storage systems,” Gao Like, a manager at the Guangxi branch of China Southern Power Grid, said in an interview with the state-owned China Central Television.

China’s JAC Group unveiled the world’s first EV powered by a sodium-ion battery in February last year. Photo: Weibo

Lithium-ion battery energy storage systems have an efficiency rate of 85 to 95 per cent.

As the world transitions towards cleaner energy sources such as wind and solar for power generation, energy storage systems can be used to enhance the flexibility and reliability of power grids, and help in the scaling-up of renewable energy.

China’s installed capacity of new-type energy storage systems, such as electrochemical energy storage and compressed air, had reached 77,680MWh, or 35.3 gigawatts as of end-March, an increase of more than 210 per cent from a year ago, according to the National Energy Administration, which is responsible for formulating the country’s energy strategy.

Lithium-ion battery energy storage accounted for more than 95 per cent of the capacity, with other emerging technologies accounting for the rest.

Although China currently dominates the global lithium-ion battery supply chain, it is highly reliant on imports of battery materials, such as lithium and cobalt.

By contrast, sodium-ion batteries are seen as a promising alternative to the resource-dependent lithium-ion batteries due to the abundance of the natural resource and low costs, as well as better performance at low temperatures and faster charging rate.

In recent years, global battery giants, including Tesla battery supplier Contemporary Amperex Technology and Japan’s Panasonic, have been exploring the use of sodium-ion batteries for different applications, from powering electric vehicles to electrical grid storage.

Once sodium-ion battery energy storage enters the stage of large-scale development, its cost can be reduced by 20 to 30 per cent, said Chen Man, a senior engineer at China Southern Power Grid.

This can be achieved through further improvements in the sodium-ion battery structure, manufacturing process, material utilisation and cycle life, thus lowering the energy storage cost per kilowatt-hour of electricity, he said.