Method for manufacturing a double-skinned plate incorporating circulation channels and plate obtained thereby

A method for manufacturing a double-skinned plate incorporating channels having at least one fluid circulation network or circuit, in particular a temperature control plate for a battery housing, said method comprising the steps of:

• providing two flat sheets or metal sheets, made of aluminum or an aluminum-based alloy,
• joining together by laser welding said two sheets into a double-skinned plate, according to a linear pattern tracing the pattern of the circulation channels, and
• forming said circulation channels by injecting a pressurized liquid or gaseous fluid between the two sheets so as to deform the zones of at least one of the sheets which correspond to said channels and which extend between the weld lines of the linear pattern,
• said method further comprising leveling or flattening the plate, having the two sheets joined by laser welding, before the step of forming, by pressure deformation, the circulation channels and in that the step of leveling or flattening the plate, having the two sheets joined by welding, is carried out by leveling in a corresponding station and comprises at least two passes in different passing or traveling directions.