I Squared Capital Invests $800M in ENTEK to Build U.S. Battery Separator Gigafactory 

Infrastructure investment manager I Squared Capital has agreed to acquire a majority equity interest in ENTEK Technology Holdings LLC, a global manufacturer of battery separators, with an $800 million investment. The capital infusion complements up to $1.3 billion in loan funding from the U.S. Department of Energy’s Advanced Technology Vehicles Manufacturing (ATVM) program. 

The investment will finance construction of a gigafactory in Terre Haute, Indiana—the first U.S. facility dedicated to producing wet-process lithium-ion battery separators, critical components for batteries powering electric vehicles, energy storage systems, defense equipment, and digital infrastructure. The project is expected to generate 763 construction jobs and 635 operational roles once completed. 

“With I Squared’s capital, strategic expertise, and global network, we will expand the U.S.’s manufacturing footprint, create high-quality jobs, and meet surging demand for batteries across critical applications, from EVs and energy storage to military defense equipment and data centers,” said Larry Keith, CEO of ENTEK. 

Gautam Bhandari, managing partner and CIO of I Squared, added: “ENTEK’s revenues are underpinned by long-term agreements with blue-chip clients, and its products are essential to U.S. re-industrialization and energy security.” 

The Terre Haute project, developed in partnership with Clayco and Brueckner Group, will produce 1.4 billion square meters of separators annually across its first two phases, with expansion capacity to 2.1 billion square meters. In addition to the DOE loan, the project has secured $200 million in 48C advanced manufacturing tax credits for Phase One and will qualify for 45X production tax credits in Phase Two. 

William Blair served as exclusive financial advisor to ENTEK. Legal counsel included Troutman Pepper Locke and Holland & Knight for ENTEK, and Kirkland & Ellis for I Squared.