BERLIN, May 12 (Reuters) – U.S. electric vehicle maker Tesla will increase its investment in battery ​cell production at its plant ‌outside Berlin by almost $250 million, boosting its capacity target for the site, the company said on Tuesday.

Tesla announced in ‌December ​investments amounting to ⁠almost 1 billion ⁠euros ($1.2 billion) at the site in Gruenheide, south-east of the German capital, as it seeks to ​bring battery cell and vehicle production all under one roof ⁠from next year.

With ⁠the latest investment, Tesla plans ​to create the conditions for annual ​production capacity of 18 gigawatt hours, ‌up from a previously planned 8 GWh.

“The ramp-up of battery cell production will also be accompanied ⁠by a significant increase in labour demand,” the company said in a statement, ⁠estimating ‌its staffing needs in ⁠battery cell production at more ​than ‌1,500 employees.

Tesla currently employs ​almost 11,000 ⁠people in Gruenheide, the company’s only gigafactory in Europe.

($1 = 0.8519 euros)

(Reporting by Christoph Steitz and Rachel More; Editing by Linda Pasquini and ​Emelia Sithole-Matarise)