NextStar Energy’s Windsor battery plant is entering its next phase of growth, expanding beyond electric-vehicle battery modules to begin producing advanced energy-storage system (ESS) batteries capable of storing renewable electricity and supplying it back to the grid during peak demand.

The facility — a $5-billion joint venture between Stellantis and LG Energy Solution — began producing battery modules in October 2024, marking a major milestone as Canada’s first large-scale EV battery manufacturing hub. Now, NextStar Energy officials say full production of ESS batteries will begin by the end of November.

ESS technology allows power generated from renewable sources like solar and wind to be stored and later released when electricity needs surge, helping stabilize grids and support the transition to cleaner energy systems.

“The energy storage system has always been on our radar here at NextStar Energy,” said chief operating officer Brett Hillock. “When we originally came up with the business model, EV was to take up 100 per cent of the capacity — but ESS was always the secondary that could be ready to load this place if needed.”

Currently, the Windsor plant is assembling battery modules using imported cells. The shift to manufacturing energy-storage units locally represents the next major operational milestone. Hillock noted the facility’s flexible production design, capable of simultaneously manufacturing both EV and ESS batteries depending on demand.

“We’re currently launching ESS based on demand from our customer,” Hillock said. “The process is not different between ESS and EV. We can either simultaneously build both products, or do one at a time.”

The expansion comes as electricity demand across North America continues to climb, driven by AI data-centre growth, electrification initiatives and rapid renewable-energy development. This surge has accelerated demand for large-scale battery storage solutions that can supply backup power and balance the grid.

With ESS production just weeks away, NextStar Energy’s strategic pivot strengthens Canada’s role in the global battery supply chain and supports the continent’s clean-energy ambitions.