China’s Contemporary Amperex Technology Ltd (CATL), the world’s top lithium-ion battery maker, plans a major boost in production of sodium-based cells, a move that will help it navigate volatility in material prices while affecting both the electric vehicle (EV) and grid-storage sectors.

The company’s planned annual production of 200 gigawatt-hours (GWh) of sodium-ion cells would represent nearly three times last year’s global production capacity, which was estimated at 70GWh, according to the International Renewable Energy Agency. One gigawatt hour is enough to power about 100 average American households for a year.

To get to that level, CATL had invested 650 million euros (US$742 million) to expand annual sodium-cell capacity by 40GWh at a plant in Fuding, in southeastern China’s Fujian province, said Amanda Xu, the firm’s head of battery energy storage systems in Europe. This was in addition to 160GWh of annual production it previously committed to at a facility in eastern Shandong province, she said.

The move comes amid increasing price volatility for the key material in the dominant lithium-ion batteries amid rising resource nationalism and supply instability.

“While energy storage becomes the critical infrastructure in our modern society, the stable and sufficient supply of raw materials plays an important role in this industry,” said William Wu, director of CATL’s energy storage system technical centre, at the introduction of an energy-storage system based on sodium batteries in Germany on Monday. “CATL is committed to promoting energy independence for all countries and regions.”

Sodium-ion batteries are seen as a viable alternative to lithium-based cells, as the core material is widely present in rocks and seawater and is by nature more resilient to cold and less prone to fire. However, sodium-ion batteries are currently not equal to lithium cells in terms of energy density and lifespan.

Access to lithium has been disrupted by export bans in some reserve-rich countries, such as Zimbabwe, as well as uncertainty surrounding mining rights in mainland China.