Factorial Energy Scales Solstice Solid-State Battery to 40 Ah Capacity

Factorial Energy has announced scaling its Solstice solid-state battery cells to a 40 Ah capacity. These A-sample cells, featuring dry cathodes, are designed for electric vehicles and represent a step forward in solid-state battery development.

Factorial Energy, supported by Mercedes-Benz, Stellantis, and Hyundai-Kia, is pursuing several development paths for solid-state batteries. In 2023, the company delivered B-sample cells with a capacity of over 106 Ah and an energy density of 391 Wh/kg. The Solstice line, currently in the A-sample phase, is expected to achieve an energy density of up to 450 Wh/kg, with the potential to increase electric vehicle range by up to 80%. The scaling to 40 Ah capacity marks progress toward commercial viability.

The company recently opened a development and production facility near Boston, which has a capacity of 200 MWh and is described as one of the largest solid-state battery production lines in the US. This facility was funded in part by a $200 million financing round led by Stellantis and Mercedes-Benz.

Factorial uses its FEST (Factorial Electrolyte System Technology) platform, which integrates a lithium metal anode and polymer separator, allowing production on existing lithium-ion battery manufacturing systems. The Solstice cells introduce a sulphide-based solid electrolyte and dry cathode process to enhance performance and scalability for future applications.

Factorial Energy collaborates with Mercedes-Benz, Stellantis, and Hyundai-Kia under undisclosed agreements as it continues to develop solid-state batteries aimed at meeting the requirements of electric vehicle manufacturers.