Factorial Energy recently announced the opening of a new manufacturing facility it claims is the largest thus far in the U.S. for solid-state batteries—although there’s not yet a timeline for scaled-up production.

Located in the Boston suburb of Methuen, Massachusetts, near Factorial’s existing headquarters and R&D center, the $50 million facility “will accommodate up to a 200 MWh assembly line,” according to a Factorial press release.

The battery cells produced on that assembly line are expected to deliver a 30% boost in energy density, in addition to various other advantages like faster charging and better thermal stability. That could mean a 50% or more range boost at the pack level, by weight.

Mercedes-Benz and Stellantis are among the companies that have invested in Factorial. At CES in January, Factorial presented a 100-amp-hour cell developed with a Stellantis partnership, a larger format than the 40-amp-hour cell Factorial had previously shown. No details on production plans were discussed, though.

Factorial cells in STLA platform

The promise of greater energy density has led other automakers to invest in solid-state batteries—to the benefit of companies developing the these batteries. Solid Power, which has gained the support of Ford and BMW, is one other such company.

Other automakers are developing solid-state batteries in-house. Honda, Toyota, and Nissan have all announced their own projects, with the intent to produce them and use them in products later in the decade. Toyota’s recently-announced timeline calls for “commercial use” in 2027 or 2028, shortly after the launch of a new generation of EVs, while Nissan aims to keep to a similar timeline.