China's first large-scale lithium-sodium hybrid energy storage station starts operation

China's first large-scale lithium-sodium hybrid energy storage station began operations on Sunday in Southwest China's Yunnan Province. This station integrates the storage advantages of lithium and sodium batteries, broadening application scenarios for sodium-ion battery storage in China and accelerating development of the new energy storage industry chain.

Compared with current mainstream lithium-ion battery storage, the newly launched lithium-sodium hybrid energy storage station - Baochi Energy Storage Station - offers a longer cycle life and operation in a wide temperature range from -20 C to 45 C, according to Science and Technology Daily.

Additionally, abundant sodium resources, which means the costs of materials are lower, provide a more economical solution for large-scale energy storage.

The Baochi Energy Storage Station spans an area of about 50 mu (3.3 hectares), roughly equivalent to five football fields, with an installed capacity of 400 megawatt-hours. Based on two charge-discharge cycles per day, the station can store and release 580 million kilowatt-hours of electricity annually, equivalent to the yearly electricity demand of nearly 270,000 households, with 98 percent sourced from green energy.

The station also uses China's first large-capacity sodium-ion battery, with a response speed six times faster than current models. Combining high-performance sodium batteries with mature lithium technology enhances the station's energy regulation capacity, CCTV News reported.

"The station serves over 30 wind and solar power plants in Yunnan. 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," Wu Bin, deputy manager of the Baochi Energy Storage Station project, was quoted by CCTV News as saying.

Yunnan is a representative region in China with a high share of renewables in its overall power supply. Currently, the installed renewable capacity in Yunnan exceeds 60 million kilowatts, with a penetration rate in the power system nearing 70 percent. A high share of renewables increases grid volatility, necessitating greater energy storage support.

As of now, China's new energy storage technologies are rapidly advancing, with lithium-ion battery storage, the most mature and cost-effective technology, dominating at 97 percent of the market, according to CCTV News.

However, growing demand for lithium batteries has raised concerns over resource shortages, as 70 percent of lithium battery materials in China come from overseas, meaning a high dependence on imports, the CCTV News report said.

In contrast, the raw materials for sodium batteries can be sourced from salt mines, seawater, and salt lakes. CCTV News reported that sodium resources in China's Chaka Salt Lake alone are 500 times greater than global lithium reserves, citing an industry expert.

Experts noted that sodium resources, besides being abundant, have more favorable properties, such as stable operation across a 45 C temperature range.