Method for controlling a battery charger (BATT) comprising a series resonance DC-DC converter (CONV) connected at its input to an input rectifier stage connected to an AC power supply network, and connected at its output to a battery (BATT), said converter (CONV) comprising: - a full bridge composed of at least two transistor arms, each of said arms comprising a top transistor (T3, T1) and a bottom transistor (T4, T2), the collectors of the top transistors (T3, T1) being connected to the positive output bus of the input rectifier stage and the emitters of the top transistors (T3, T1) being connected to the respective ends of a series resonant circuit comprising a capacitor, an inductor and a primary winding of a transformer, the collector of each bottom transistor (T4, T2) being connected to the emitter of the top transistor (T3, T1) in the same arm as said bottom transistor (T4, T2), and the emitter of each bottom transistor (T4, T2) being connected to the negative output bus of the input rectifier stage, - said series resonant circuit, - said transformer whose primary winding is connected to the full bridge and whose secondary winding is connected to the input of an output rectifier, - circuits to aid the switching at zero voltage of said top (T3, T1) and bottom (T4, T2) transistors, - and said output rectifier connected at its output to said battery (BATT) said method comprising: - a step for controlling the opening of one of said top transistors, - a step for controlling the closing of one of said bottom transistors in the same arm as said one of said top transistors a dead time (Tm) after said step for controlling the opening, characterized in that said step for controlling the closing is conditioned to a test step carried out on the time variation of an estimation of the voltage across the terminals of said one of said bottom transistors during said dead time (Tm), and during said test step, the time variation of said voltage is analyzed, said step for controlling the closing only being triggered when said voltage is detected to be increasing and when said voltage is furthermore in the range between a predetermined low voltage threshold and high voltage threshold (Sh). - a full bridge composed of at least two transistor arms, each of said arms comprising a top transistor (T3, T1) and a bottom transistor (T4, T2), the collectors of the top transistors (T3, T1) being connected to the positive output bus of the input rectifier stage and the emitters of the top transistors (T3, T1) being connected to the respective ends of a series resonant circuit comprising a capacitor, an inductor and a primary winding of a transformer, the collector of each bottom transistor (T4, T2) being connected to the emitter of the top transistor (T3, T1) in the same arm as said bottom transistor (T4, T2), and the emitter of each bottom transistor (T4, T2) being connected to the negative output bus of the input rectifier stage, - said series resonant circuit, - said transformer whose primary winding is connected to the full bridge and whose secondary winding is connected to the input of an output rectifier, - circuits to aid the switching at zero voltage of said top (T3, T1) and bottom (T4, T2) transistors, - and said output rectifier connected at its output to said battery (BATT) - a step for controlling the opening of one of said top transistors, - a step for controlling the closing of one of said bottom transistors in the same arm as said one of said top transistors a dead time (Tm) after said step for controlling the opening,