Tesla confirmed by US govt as mystery buyer in $4.3 billion LG Energy Solution deal for domestic Megapack 3 production

The U.S. Department of the Interior (DOI) has officially confirmed that Tesla is the customer behind a landmark $4.3 billion supply agreement with LG Energy Solution (LGES). The announcement, made during the Indo-Pacific Energy Security Summit, solidifies a strategic pivot for Tesla as it moves to onshore its supply chain for large-scale energy storage. 

The deal was first hinted at in regulatory filings in August 2025. It involves the supply of lithium iron phosphate (LFP) battery cells manufactured at LGES’s facility in Lansing, Michigan.  

While the initial filing only referred to an “unnamed overseas client,” industry analysts and pv magazine / ESS News contributors had long pointed toward Tesla. 

A primary driver for the partnership is the mitigation of rising U.S. tariffs on Chinese imports. By sourcing LFP cells from Michigan rather than China-based giants like CATL, Tesla ensures its Megapack energy storage systems remain cost-competitive and compliant with domestic content requirements under the Inflation Reduction Act (IRA). 

 LFP chemistry is particularly favored for stationary storage due to its safety profile and cycle life. It has historically been dominated by Chinese manufacturing. 

The contract is set to begin on August 1, 2027, and run through July 31, 2030. Provisions within the agreement allow for a potential seven-year extension, which could see LGES supplying Tesla through 2037. 

The Michigan-made cells will be integrated into Tesla’s Megapack 3 units at its assembly plant in Houston, Texas. This is expected to significantly reduce lead times and logistics costs for utility-scale solar-plus-storage projects across North America. 

To meet the demand, LGES is converting its Lansing site into a specialized hub for prismatic LFP cells. Once operational, the site will make LGES the first global manufacturer to offer all three major form factors (pouch, cylindrical, and prismatic) from a single domestic footprint. 

From pv magazine USA.