China activates first large-scale sodium-ion battery

China has started operation of its first large-scale sodium-ion battery storage station, the company operating the battery has announced.

China Southern Power Grid Energy Storage, the unit that acts as the energy storage arm of grid operator China Southern Power Grid (CSPG), said it had put a 10 MWh sodium-ion battery in Nanning into operation on May 11. The station uses than 22,000 sodium battery cells of 210 Ah capacity that can be charged to 90 percent in 12 minutes, CSPG Energy Storage said in a statement.

The station, built by CSPG's Guangxi branch, is the first phase of a project that will have 100 MWh capacity when complete. The full project will be able to provide 73 million kWh of clean power a year, enough to meet the power requirements of 35,000 residential customers and eliminating 50,000 tonnes of carbon dioxide emissions, CSPG Energy Storage said.

China's new energy storage projects have reached cumulative installed capacity of 35.3 million kWh by the end of March 2024, with electrochemical storage, including lithium-ion batteries, accounting for more than 95 percent of the storage capacity.

In its statement, CSPG Energy Storage pointed out that sodium-ion batteries and lithium-ion batteries both have similar electrochemical mechanisms, but that raw material for sodium-ion batteries is much more abundant, costs less and is easier to extract. The batteries also perform better at lower temperatures, giving them advantages in large-scale energy storage.

Chen Man, a technical expert at CSPG, said large-scale deployment of sodium-ion batteries can help reduce costs by 20 percent to 30 percent, bringing cost per kWh of electricity to $0.0276, or just above two US cents per kWh.