MADRID (Reuters) - Stellantis ( STLA ) and Chinese battery maker CATL will invest 4.1 billion euros ($4.33 billion) in a factory making electric vehicle batteries in Zaragoza in northern Spain, they said in a statement on Tuesday.

They have set up a 50-50 joint venture for the project and expect to start production by the end of 2026.

The capacity at the plant could reach 50 gigawatt hours, depending on the evolution of the market for electric vehicles in Europe and on support from European and Spanish authorities, they said.

The venture would bring "innovative battery production to a manufacturing site that is already a leader in clean and renewable energy," Stellantis's ( STLA ) chairman John Elkann said.

He thanked Spanish authorities for their support.

Robin Zeng, CATL's chairman and CEO, was in Madrid on Monday, where he met with Prime Minister Pedro Sanchez.

Stellantis ( STLA ) is also the largest investor in the ACC battery making joint-venture together with Mercedes and French oil company ToatalEnergies. ACC has started production at a gigafactory in France, while the development of two other gigafactories, in Italy and Germany, has been stalled due to low demand for electric vehicles.

($1 = 0.9472 euros)