美国政府加码硅负极电池投资：DOE向Coreshell拨款5000万美元建设2GWh电池工厂

Last week, the Department of Energy awarded a $50 million grant to Coreshell Technologies, a General Motors–backed California startup whose battery would replace graphite with raw silicon. The money will help Coreshell build a 2 gigawatt-hour battery gigafactory, initially aimed mostly at powering drones and military equipment on naval ships, CEO Jonathan Tan told me.

Though a modest award, the money reflects a growing U.S. bet on next-generation silicon anode batteries to counter China’s control of more than 90% of the world’s battery-grade graphite, the material used to make almost all battery anodes. The objective is to replace a large portion of the graphite anodes with silicon ones and begin to build up a U.S. battery materials and components industry.

Earlier this month, the Pentagon awarded a[conditional $1.4 billion loan](https://www.theinformation.com/newsletters/the-electric/trump-puts-pentagon-loan-behind-next-generation-batteries-leapfrog-china?rc=fd9gxc) to Sila Nanotechnologies, a California startup that would use the funding to expand its silicon anode manufacturing plant in Washington state. The government is following investors into the sector: In July, Sila raised $300 million in venture funds. Coreshell raised a $46 million Series B round in March. Shares of U.S. silicon anode battery maker Amprius Technologies are up 28% over the last year.

It is highly unlikely that U.S. silicon-anode and battery startups like Coreshell, Sila, Amprius and others will push Chinese graphite anodes out of the U.S. market. But Coreshell’s Tan claims that the startup’s battery reflects a breakthrough in silicon anodes that makes them cheaper than China’s graphite ones. If that’s true, silicon anode batteries could capture a serious share of the U.S. market over time.

The administration’s investments reflect how China has used graphite in an escalating trade war with the U.S. In 2023, China imposed export controls on virtually all grades of raw graphite used to make battery anodes in a tit-for-tat trade battle with the U.S. Last October, the U.S. announced a new blacklist of Chinese companies banned from buying high-end AI chips, and Beijing escalated its export controls to include processed battery-grade graphite and the processing equipment itself.

Later in October, both the U.S. and China suspended their new chip and graphite export restrictions until this coming November to allow time to negotiate a trade deal. There is no indication so far that either side will back down, however, leading U.S. foreign policy experts and industry veterans to expect the expanded graphite export controls will take effect.

Meanwhile, silicon anodes are attracting the attention of drone, electronic device and electric vehicle makers because they deliver much more energy than graphite ones and do so faster. This is because silicon molecules can hold 10 times as much lithium as graphite ones, and silicon anodes do not gum up when they are charged rapidly. Drones based on silicon anodes can fly further, flying electric taxis can quickly recharge to allow for frequent use, and smartphones can run all their AI features.

Silicon anodes are generally far more expensive than graphite ones, however. This is because they tend to swell massively during the charging cycle, leading to cracks in the anode and the failure of the battery, so they must be engineered to contain this expansion.

Tan, however, claimed that Coreshell’s batteries use cheap raw metallurgical silicon and do not require engineered anodes. Among features that absorb the swelling, he said that Coreshell uses a stretchy coating, which holds the silicon together so pieces of it don’t break off, and a cell structure that creates more room for the silicon.

The DOE awarded Coreshell the $50 million grant under a Biden–era infrastructure program. Tan expects it will take until December or so to negotiate contract details with the department and three years after that to scale up the plant in stages.

Coreshell is promising an entirely new type of battery, though one that can be manufactured on standard lithium-ion production lines. It will make them in partnership with AM Batteries, a developer of dry iron–based cathodes that cut manufacturing costs while boosting energy density. Conventional cathodes are made using toxic solvents in a slurry; dry cathodes leave out the wet solvent, along with the requirement for large and expensive drying ovens.

Dry cathodes, however, are extraordinarily difficult to make at scale because almost nothing is binding the cathode powder to its metal substrate. Only one major battery in the world is believed to currently use such cathodes—the one that powers the Tesla Cybertruck.

Coreshell’s chief technology officer, Hieu Duong, invented dry cathodes in 2018 while at a San Diego startup, Maxwell Technologies, then went to work at Tesla, which bought Maxwell in 2019. He went to AM in 2023. That year, AM was named to[The Information’s 50 Most Promising Startups](https://www.theinformation.com/projects/the-information-50-2023) list. Duong told me that the battery AM is making with Coreshell will be AM’s first commercial deployment.

Tan said the combination of the two technologies—Coreshell’s metallurgical silicon anode and AM’s dry cathode—would make the resulting battery competitive with conventional Chinese lithium-iron-phosphate batteries on price and performance. He said the battery would also easily surpass the energy density of Chinese LFP, reaching roughly 260 watt-hours per kilogram, compared with 200 Wh/kg for state-of-the-art Chinese LFP batteries. He declined to disclose Coreshell’s expected manufacturing costs.

“If the U.S. as a whole is going to try to take a competitive approach against Chinese product, and their ability to drive pricing at such a ferocious pace, it’s going to need technologies that offer something fundamentally differentiated that give them an edge,” Tan said.