[DigitalToday reporter Jinju Hong (홍진주)] The electric vehicle battery industry is paying attention first to commercialising silicon anode technology rather than solid-state batteries, which have been seen as next-generation technology. Automakers and battery companies are expanding the use of silicon anodes, expecting longer driving range and faster charging.

InsideEVs, an electric vehicle specialist outlet, reported on June 18 that General Motors is viewing wider use of silicon anodes as a leading solution for short- and medium-term next-generation battery technology.

Kurt Kelty, GM's head of batteries and sustainability, said at the 'GM Empower Conference' in San Francisco that he believes silicon is the next-generation anode technology. He said a trend is likely to emerge in which silicon anodes take a larger share in the short to medium term.

The anode is a core battery component that stores lithium ions during charging and releases them again during discharge. Most anode materials used in current EV batteries are graphite. Graphite has strengths in stability and energy density, but its weakness is that mining and processing are concentrated in certain countries. More than 90 percent of global processing of battery-grade graphite is concentrated in China, and supply chain risks have been raised consistently. The industry expects energy density to improve significantly if the share of silicon is raised in place of graphite.

Silicon can store more lithium ions in the same volume, which is advantageous for increasing driving range and improving charging speed. Its volume expands significantly during charging, so research has mainly focused on mixing silicon with graphite rather than using pure silicon.

Silicon anode technology has already entered partial commercialisation. The technology is being applied to premium smartphone batteries, and its use is expanding in automotive batteries as well.

The industry sees solid-state batteries as still requiring several more years before full-scale commercialisation. As a result, silicon anodes are drawing attention as a realistic next-generation battery technology.

Battery companies are also presenting performance improvement effects. U.S. battery startup Amprius Technologies claimed that an EV that can drive about 310 miles on a conventional battery could extend its range to as much as 574 miles by applying its silicon anode battery. Another U.S. company, Sila, said applying high-silicon anode material could improve driving range by about 20 percent without increasing the size of the battery pack.

Examples of use in actual vehicles are also emerging. Britain's ultra-high-performance electric hypercar McMurtry Speirling implemented performance that reaches 60 miles per hour from a standstill in 1.55 seconds by applying silicon anode technology from Group14 and Molicel.

Mercedes-Benz has also applied a silicon-containing anode to its new AMG GT electric vehicle. The company explained it can charge from 10 percent to 80 percent in about 11 minutes through ultra-fast charging of up to 600 kW.

The industry's challenge is mass production and improving price competitiveness. Silicon anode batteries are currently being applied mainly to high-performance vehicles, but the industry is pushing measures to expand use into the mass-market EV segment. Sila secured silicon anode material production capacity at its Moses Lake plant in Washington state to supply up to 50,000 EVs a year. It plans to expand capacity to as much as 2.5 million vehicles as demand rises. The company has already signed supply contracts with major companies including Mercedes-Benz and Panasonic.

Group14 has also begun mass production of silicon anode materials through a production facility in South Korea that it set up as a joint venture with SK. The plant is designed for up to 10 GWh a year and is assessed as being able to supply battery materials for more than 100,000 EVs.

GM is maintaining a strategy of not relying on a single battery chemistry. Kelty said the company will use a combination of various battery technologies depending on vehicle use. GM is currently applying high-nickel batteries to its main EVs, and uses lithium iron phosphate batteries in the Chevrolet Bolt. It also plans to apply low-cost lithium manganese-rich batteries to large SUVs and pickup trucks scheduled for release in 2028. It recently disclosed plans to develop sodium-ion batteries for grid energy storage systems.

It is also conducting solid-state battery research in parallel. Kelty said, "We have multiple solid-state battery prototypes in the lab and testing is under way," and added, "We always need to check what the latest technology is."

The industry sees EV battery competition as unlikely to end with a single technology. Silicon anodes are emerging as a practical technology that can improve driving range and charging performance immediately, while development of solid-state batteries is continuing as a longer-term next-generation technology. As a result, expansion of mass production, cost reductions and the pace of adoption in mass-market models are expected to be key competitive factors for silicon anode batteries in the EV market.