---
title: Samsung SDI Takes Full Ownership of GM's $3.5 Billion Indiana Battery Plant
description: GM has sold its stake in the New Carlisle battery plant to Samsung SDI, which will pivot it to grid storage as US EV demand slows.
author: Darie Nani (Editor-in-Chief)
updated: 2026-08-17T15:19:59.653Z
canonical: https://www.sovereignmagazine.com/article/samsung-sdi-gm-indiana-battery-plant-buyout
categories: Green Tech
content_type: News
region: United States
publication: Sovereign Magazine
schema_type: Article
---

General Motors has sold its 49.99% stake in the New Carlisle, Indiana battery factory to its partner Samsung SDI, ending the automaker's ownership in the $3.5 billion plant and handing the Korean cell maker its first wholly owned battery base in North America. The two companies announced the partnership in April 2023 and finalized the joint venture, filed as SDI-GM Synergy Cells Holdings, in 2024. Neither disclosed the purchase price.

When GM and Samsung SDI drew up the 680-acre site, the plan was 27 gigawatt-hours of annual capacity, scalable to 36, more than 1,600 jobs, and mass production of nickel-rich prismatic cells for GM's electric vehicles starting in 2027. That demand has not arrived on schedule, and the ownership change is the clearest sign yet of how far US automakers have pulled back.

## GM Stopped Funding Capacity It No Longer Expects to Fill

A Samsung SDI official tied the handover directly to the market, saying the change "was made in consideration of market changes since the joint venture was announced, including the slower-than-expected growth of EV demand."

The retreat is broad. US automakers cut electric-vehicle production after the $7,500 federal EV tax credit expired on September 30, 2025. GM has taken a charge of roughly $6 billion as it scaled back its EV plans, and its other major cell bet, the Ultium Cells venture with LG Energy Solution, has spent the past year idling lines and recalling workers. Selling out of New Carlisle lets GM stop funding capacity it no longer expects to fill on the original timeline, while keeping a supply relationship with the plant's new sole owner.

## Samsung SDI Will Open the Plant Making Storage Batteries, Not EV Cells

For Samsung SDI, full control is a chance to repurpose the plant. It is still under construction, and the company now plans to open it by producing energy storage system batteries for the US market rather than the EV cells that defined the original plan. The move fits a wider shift among Korean cell makers, which are steering resources toward stationary storage as the EV slowdown bites and grid-scale and data-center power demand outpaces the US EV take rate. Korean business press has described energy storage as offering stronger near-term growth than electric vehicles for the same manufacturers.

Samsung SDI shares fell roughly 4.5% on the news, reflecting the cost of absorbing a half-built plant on its own and the risk of standing up a new product line before the EV volumes it was meant to serve arrive.

## The Prismatic EV Cells Are Deferred, Not Cancelled

The EV cells have been put off, not dropped. Alongside the ownership change, Samsung SDI and GM signed a separate agreement to co-develop next-generation prismatic battery cells made for high energy density and fast charging, aimed at potential future electric vehicles. Those cells, which Samsung SDI markets under its PRiMX brand, use a rigid rectangular casing that the company says improves packaging efficiency, durability and system integration, and the New Carlisle site could add them later once demand recovers.

A plant designed around prismatic EV cells will earn its first revenue from energy storage instead, with the EV line held behind a co-development agreement rather than a firm production start. The plant will run on storage demand now, and wait for EV demand to recover.

## FAQ

**Q: What is a prismatic battery cell, and how does it differ from cylindrical and pouch cells?**
A prismatic cell packs its electrodes into a rigid, flat rectangular case. That shape lets many cells stack tightly into a pack with little wasted space, the packaging advantage cited here. Cylindrical cells are small metal tubes that leave gaps when grouped, while pouch cells use a soft foil casing that saves weight but needs more external support. Prismatic and cylindrical formats trade some flexibility for the structural rigidity that aids durability and cooling.

**Q: What is an ESS battery, and why is demand for it rising in the US?**
ESS stands for energy storage system: large stationary battery installations that store electricity for the grid, businesses or facilities rather than powering a vehicle. They bank surplus power, including from solar and wind, and release it when demand peaks. US interest has climbed as grid operators add renewables that need backing up and as data centers add large new electricity loads that storage can help balance.