Automotive Cells Company (ACC) has produced its five-millionth battery cell at its plant in Douvrin, France, the company has announced. The milestone lands as the joint venture prepares its second production block at the site, a 12.9 GWh line scheduled to start production in 2027.

ACC is a three-way battery joint venture between Stellantis, Mercedes-Benz and TotalEnergies. The five-million-cell figure covers output at the French plant since serial production began there. The company frames the milestone as "Made in France" — a positioning that carries weight in European industrial policy circles, where localized cell production has become a condition for EV value-chain subsidies.

What does the 12.9 GWh second block mean?

The second production block is the concrete capacity story here. At 12.9 GWh, it would add substantial volume to the site's existing output, and its 2027 start date anchors ACC's ramp timeline in a program that European automakers are watching closely as they localize battery supply.

A 2027 launch puts the second block roughly in line with the next wave of European EV programs. For Stellantis and Mercedes, both ACC shareholders and its anchor customers, cells from Douvrin feed dedicated electric platforms built in European plants.

The announcement is a company claim, and ACC — like every cell maker scaling in Europe — has faced questions about ramp pace versus announced schedules. The five-millionth cell is a verified production count from the manufacturer itself; the 12.9 GWh second block remains an announced intention, with its timing stated by ACC rather than independently confirmed against output data.

Why the cell count matters

Five million cells is a cumulative production marker, not a capacity figure. It signals that the first block at Douvrin has moved beyond pilot-scale output into sustained series production. For a joint venture backed by two major OEMs and one of Europe's largest energy groups, that distinction matters: European cell startups have struggled to convert announced gigafactory plans into consistent output, and cumulative counts are one of the few hard indicators available.

The milestone also lands at a sensitive moment for European battery manufacturing. Demand forecasts for EV cells have softened industry-wide, and several programs across the continent have delayed or scaled back capacity plans. Against that backdrop, ACC's decision to keep the second block on a 2027 timeline — as stated in the announcement — is the most commercially significant element of the news.

What to watch next

The dates that will define this program:

• 2027: Start of production at the Douvrin second block, adding 12.9 GWh of nameplate capacity.
• Ramp verification: Whether cumulative cell output continues to climb at pace once the second block comes online.
• Customer allocation: How Stellantis and Mercedes split cell supply from the expanded French site across their European EV lines.

The five-million-cell milestone confirms the first block is producing. The 2027 second block will show whether ACC can scale on schedule — the test that has tripped up most of its European peers.