A panel of exterior cladding of a building including: - an upper transverse edge including an upper overlap area intended to be overlapped by an adjacent panel, - a lower transverse edge including a lower overlap area intended to overlap an adjacent panel, - a central part, which connects the transverse edges, which is covered by at least one pair of columns of photovoltaic modules, each column including one electrical pole at one of its longitudinal extremities and one electrical pole of inverse polarity at the other extremity, the poles of the two adjacent columns being of inverse polarity, - a perforation situated in the lower overlap area through which a conducting strip passes, which connects one of the two electrical poles of the column of photovoltaic modules to one of the two shells (12, 13) of a connection box, this shell being situated on the rear side of the panel in the lower overlap area, - an indentation, situated in the upper overlap area in which the other of the two shells (12, 13) of the connection box is placed, this shell being connected to the other electrical pole of the column of photovoltaic modules, the connection box including a first shell and a second shell, one interlockable inside the other, - the first shell including: ∘ a base including one aperture topped by a sealing chamber, ∘ a lateral wall surrounding the base and extending perpendicularly to it, the lateral wall including a removable hatch used as a wire passage, ∘ an electrical terminal connected to the base, with an axis perpendicular to the base, - the second shell including: ∘ a base, ∘ a lateral wall surrounding the base and extending perpendicularly to it, the lateral wall including a wire passage, ∘ an electrical terminal of inverse polarity to that of the electrical terminal of the first shell, the electrical terminal having an axis perpendicular to the base, connected to the base and positioned in such a way that it is plumb with the electrical terminal of the first shell when the first and the second shell are interlocked. - an upper transverse edge including an upper overlap area intended to be overlapped by an adjacent panel, - a lower transverse edge including a lower overlap area intended to overlap an adjacent panel, - a central part, which connects the transverse edges, which is covered by at least one pair of columns of photovoltaic modules, each column including one electrical pole at one of its longitudinal extremities and one electrical pole of inverse polarity at the other extremity, the poles of the two adjacent columns being of inverse polarity, - a perforation situated in the lower overlap area through which a conducting strip passes, which connects one of the two electrical poles of the column of photovoltaic modules to one of the two shells (12, 13) of a connection box, this shell being situated on the rear side of the panel in the lower overlap area, - an indentation, situated in the upper overlap area in which the other of the two shells (12, 13) of the connection box is placed, this shell being connected to the other electrical pole of the column of photovoltaic modules, the connection box including a first shell and a second shell, one interlockable inside the other, - the first shell including: ∘ a base including one aperture topped by a sealing chamber, ∘ a lateral wall surrounding the base and extending perpendicularly to it, the lateral wall including a removable hatch used as a wire passage, ∘ an electrical terminal connected to the base, with an axis perpendicular to the base, ∘ a base including one aperture topped by a sealing chamber, ∘ a lateral wall surrounding the base and extending perpendicularly to it, the lateral wall including a removable hatch used as a wire passage, ∘ an electrical terminal connected to the base, with an axis perpendicular to the base, - the second shell including: ∘ a base, ∘ a lateral wall surrounding the base and extending perpendicularly to it, the lateral wall including a wire passage, ∘ an electrical terminal of inverse polarity to that of the electrical terminal of the first shell, the electrical terminal having an axis perpendicular to the base, connected to the base and positioned in such a way that it is plumb with the electrical terminal of the first shell when the first and the second shell are interlocked. ∘ a base, ∘ a lateral wall surrounding the base and extending perpendicularly to it, the lateral wall including a wire passage, ∘ an electrical terminal of inverse polarity to that of the electrical terminal of the first shell, the electrical terminal having an axis perpendicular to the base, connected to the base and positioned in such a way that it is plumb with the electrical terminal of the first shell when the first and the second shell are interlocked.