Abstract: A device for connecting an electric line to a connection terminal for direct or indirect connection with a circuit breaker, which comprises at least one first electrically conducting body having a first end portion intended to be operatively connected to the terminal, and a second end portion intended to be operatively connected to a conductor element of the electric line, and at least one thermal conducting body comprising a hermetically sealed cavity containing a cooling fluid. The thermal conducting body is operatively coupled to the first electrically conducting body such that the hermetically sealed cavity has a first surface arranged in proximity to the first end portion and a second surface arranged in proximity to the second end portion.