China switches on first large-scale lithium-sodium hybrid storage project

Chinese state-owned grid operator China Southern Power Grid has switched on the country’s first large-scale lithium-sodium hybrid energy storage station, a 200MW/400MWh behemoth combining both lithium-ion and sodium-ion battery technology.

Located in the Yunnan Province of southwest China and operated by the smaller of the country’s two grid operators, China Southern Power Grid, the Baochi Energy Storage Station covers an area measuring over 3 hectares, equivalent to five soccer fields.

The new hybrid storage station, which began operations on Sunday, is capable of two charge-discharge cycles each day, and is capable of storing up to 800 MWh of electricity per day, roughly equivalent to the electricity demands of 270,000 households.

Importantly, China Southern Power Grid claims that the Baochi Energy Storage Station utilises 98 per cent renewable energy to charge.

“The station serves over 30 wind and solar power plants in Yunnan,” said Wu Bin, deputy manager of the Baochi Energy Storage Station project, according to the Global Times.

“The lithium-sodium hybrid technology enables more stable integration of large-scale renewables into the power grid and supports future participation in electricity market trading.”

The project is also using China’s first large-scale sodium battery developed in the country and boasts a response speed six times faster than other sodium-ion batteries.

 Start of operations for the Baochi Energy Storage Station marks a milestone for China’s battery storage sector as it seeks to diversify its technological dominance ahead of expected supply constraints on lithium battery materials.

Tthe raw materials for sodium batteries can be easily sourced from salt mines, seawater, and salt lakes, an abundant resource which reduces material costs and opens the door for a more economical large-scale energy storage option. Sodium batteries are also a safer battery material, with stable operations from -20°C to 45°C.