E-Power Inc. (NASDAQ: EPOW) received a patent for a multi-element doped hard carbon composite material designed for sodium-ion battery anodes. The patent, numbered CN2023105784527, covers a phosphorus-silver-silicon co-doped hard carbon composite and its preparation method.

The patented material combines silicon for enhanced capacity, silver for improved conductivity, and phosphorus for interface regulation within a hard carbon matrix. According to the company, this combination addresses volume expansion issues typical of silicon during sodium storage while managing conductivity limitations of standard hard carbon materials.

Hard carbon serves as the preferred anode material for sodium-ion battery commercialization due to its structural properties that allow sodium ion intercalation, which traditional graphite cannot accommodate. The company's approach involves multi-element doping rather than the conventional pitch or resin co-carbonization methods.

"The P-Ag-Si/HC technology provides a sophisticated answer to the stability and conductivity challenges in sodium-ion batteries," said Haiping Hu, chairman of E-Power, in a statement.

E-Power operates through a joint venture that manufactures graphite anode materials for lithium-ion batteries. The company has a manufacturing facility with 50,000 tons of production capacity that uses renewable energy sources.

The patent grant follows the company's strategy to diversify its battery material portfolio as the industry explores sodium-ion alternatives to lithium-ion technology. Information in this article is based on a company press release.