Samsung SDI will acquire General Motors' 49.99% stake in SynergyCells, taking full ownership of the $3.5 billion battery plant under construction in New Carlisle, Indiana and turning it into the company's first standalone production base in North America. The venture, launched in 2024 with planned annual capacity of 27 GWh and a 2027 start, will be renamed Samsung SDI SynergyCells Holdings and will initially produce batteries for energy storage systems as North American EV demand grows more slowly than expected. Samsung SDI and GM are still maintaining a technology partnership. The companies signed a joint development agreement to co-develop next-generation prismatic batteries using Samsung SDI's high energy density and fast-charging technologies for potential future GM EV applications, and Samsung SDI said the Indiana site could eventually produce those cells. The shift follows a 33% year-over-year drop in GM's U.S. EV sales in the second quarter, a $6 billion impairment charge in the fourth quarter last year tied to its EV business, and broader pressure after the loss of a $7,500 U.S. EV purchase subsidy last September.