Abstract: The invention relates to a method of producing electrical connections for an electrical energy storage unit (10), said unit employing at least one electrical energy storage element (70) placed inside a casing (20?), said casing having at least one cover (30, 40) containing the electrical energy storage element (70) in a main body (20) of the casing, said element (70) and said cover (30, 40) each having a current collector means, which method is characterized in that it includes at least one step of depositing gallium on one or other of the current collector means and a step of assembling two current collector means separated by the gallium coating followed by a diffusion brazing step carried out by the disposition and the pressing of a mass heated to a given temperature on the unit formed by two current collector means, the unit being brazed for a given time in order to produce the electrical connection for the electrical energy storage unit.