---
title: A $3.5 Billion Battery Plant Built for EVs Will Open Making Grid and Data-Center Batteries Instead
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)
date: 2026-08-21T12:14:32.717Z
updated: 2026-08-21T12:14:32.723Z
canonical: https://www.sovereignmagazine.com/article/samsung-sdi-gm-indiana-battery-plant-buyout
image: https://cdn.nanimediahouse.com/unsplash-a-bunch-of-black-and-white-objects-with-a-green-arrow-above--73taIS3YeNQ.jpg
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 its ownership of a $3.5 billion plant designed to mass-produce cells for its electric vehicles. The plant, still under construction, will now open making energy storage batteries for the grid and data centers. Neither company disclosed the price.

The sale hands Samsung SDI its first wholly owned battery base in North America and closes out a joint venture, filed as SDI-GM Synergy Cells Holdings, that the two companies announced in April 2023 and finalized in 2024. The original plan for the 680-acre site 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.

## The EV Demand Slowdown

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."

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's Pivot to Energy Storage

Full control gives Samsung SDI room to repurpose the plant, and it plans to open it by producing energy storage system batteries for the US market. Korean cell makers broadly are steering resources toward stationary storage, where grid-scale and data-center power demand is growing faster than US EV sales, and 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 Cell Agreement

Alongside the ownership change, Samsung SDI and GM signed a separate agreement to co-develop next-generation prismatic battery cells designed 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. The New Carlisle site could add them once EV demand recovers, so GM keeps a route back to the plant's original purpose without funding it in the meantime.

## 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.