Method for welding cell interconnectors, and welding electrode arrangement for said method

A method for welding in each case one interconnector of two adjacent electrochemical cells of a rechargeable battery, in particular a lead acid rechargeable battery,

• wherein the two electrochemical cells are disposed so as to be separated from one another by means of a housing partition, wherein the interconnectors are disposed so as to face one another on two opposite sides of the housing partition, wherein an opening is disposed in a region of the housing partition where the interconnectors are opposite one another, and wherein the method comprises the following steps:
• contacting the interconnectors with a welding electrode arrangement, wherein the welding electrode arrangement has at least one pair of welding electrodes, wherein one welding electrode of the at least one pair of welding electrodes contacts in each case one of the interconnectors by means of an insert part;
• welding the interconnectors in such a manner that, by means of a pressure applied by the insert parts of the welding electrodes and a current applied to the welding electrode arrangement, the material of the interconnectors melts at least in regions and is connected in a materially bonded manner through the opening in the housing partition, specifically so that the generated welding area has an area proportion of plastics inclusions of at most 8% in the welding area.