Ferroglobe develops high-purity silicon metal powder for battery applications

MADRID—Ferroglobe P.L.C., the largest producer of refined silicon metal in the western hemisphere, has developed a high-purity silicon metal powder for use in battery anodes and other advanced technologies.

The polycrystalline silicon powder grade achieved by Ferroglobe, based in London with quartz mines and refineries across the globe, is 99.995 percent pure (in micrometer and sub-micrometer size), according to the company.

The milestone was achieved at the company's innovation center in Sabon, Spain, a facility equipped with "cutting-edge, proprietary technologies in silicon melting, silicon metal purification and silicon powder particle size reduction."

Ferroglobe had been working on the refinement project for about five years when the breakthrough was announced July 7.

"Our company has succeeded in producing a silicon metal powder that stands out for its extremely high purity, and now we must go one step further," said Benoist Ollivier, chief technology and innovation officer at Ferroglobe. "It is time to start offering the market our industrial capacity for global production of this critical material for the advancement of innovative, cost-effective and low-carbon footprint solutions to accelerate the energy transition."

Ferroglobe said the refinement process for the high-purity silicon metal powder has no secondary chemical flow, "ensuring sustainability throughout the entire value chain."

"The strategic importance of Ferroglobe's battery silicon project already was recognized in 2021 by the European Commission, including ... in the IPCEI European Battery Innovation," the company said.

To further develop certain applications for the anodic material, Ferroglobe is working with several industry leaders and startups.

They include E-magy, a manufacturer of nano-porous silicon; Sicona, which has pioneered a manufacturing process for high-performance silicon-graphite-carbon composite anode materials; Granode Materials, which is developing a new graphene-based anode material; Altech, which is engaging in a feasibility study for the construction and operation of a 10,000-metric-tons-per-year silicon/graphite alumina coating plant in Germany; and Advano, which works with silicon materials for lithium ion batteries in the EV and consumer electronics industries.

In concert with these partnerships and co-ops, Ferroglobe will continue to supply its knowledge from the innovation center in Spain and a refinement facility in Montricher, France, where initial industrial capacity of the refined silicon metal powder is being produced.

Ferroglobe, which produces about 275,000 tons of refined silicon metal per year, maintains North American refineries in Alloy, W.Va. (a joint venture with Dow); Selma, Ala.; Beverly, Ohio; and Quebec, Canada (also a JV with Dow).

Ferroglobe maintains quartz mines in North and South America, and Spain, along with other metallurgy facilities (refineries) in South America, South Africa, Spain, France, Scandinavia and Asia.

Silicon dioxide, from which silicon metal is refined, is one of the most ubiquitous materials in the Earth's crust, derived from quartz rock or sand, so it is not nearly as finite in its mining capacity as lithium, cobalt or manganese—other elements that are increasing in demand as the EV revolution sets in and demand remains high in the metal alloy industry.