Modular device for conversion of electrical energy for implementing the recharging of an electrical battery, or user battery, using an AC line supply and supplementary sources of electrical energy, said supplementary sources of electrical energy being for example formed by buffer batteries, by flywheel accumulators, by photovoltaic generators or by any other source of electrical energy, characterized in that it comprises: - a plurality of switching modules (122a, 122b, 122c, 13, 14), with a substantially identical structure, each switching module being associated with one of the available sources of electrical energy (61, 59) and producing, by chopping the voltage delivered by the source with which a DC voltage of given value is associated; - a power DC bus comprising two electrical lines (23, 24), to which each of the various available sources of electrical energy is connected by means of the switching module which is associated with it, each switching module being composed of two electronic switches configured in series between the two lines (23, 24) of the power DC bus, - a control circuit which generates the chopping controls applied to the switches of the various switching modules (122a, 122b, 122c, 13, 14), the chopping control applied to a given switching module being defined by a control law which depends on the voltage and on the charge current necessary for performing a recharging of the electrical battery in question and on the maximum power available from the AC line supply; - an accommodation structure configured for receiving the various switching modules and forming the power DC bus, said accommodation structure comprising a plurality of functionally identical locations onto which the various switching modules can be placed; and in that the chopping controls generated by the control circuit are square-wave signals having a duty cycle which varies as a function of the value of the voltage to be established on the power DC bus. - a plurality of switching modules (122a, 122b, 122c, 13, 14), with a substantially identical structure, each switching module being associated with one of the available sources of electrical energy (61, 59) and producing, by chopping the voltage delivered by the source with which a DC voltage of given value is associated; - a power DC bus comprising two electrical lines (23, 24), to which each of the various available sources of electrical energy is connected by means of the switching module which is associated with it, each switching module being composed of two electronic switches configured in series between the two lines (23, 24) of the power DC bus, - a control circuit which generates the chopping controls applied to the switches of the various switching modules (122a, 122b, 122c, 13, 14), the chopping control applied to a given switching module being defined by a control law which depends on the voltage and on the charge current necessary for performing a recharging of the electrical battery in question and on the maximum power available from the AC line supply; - an accommodation structure configured for receiving the various switching modules and forming the power DC bus, said accommodation structure comprising a plurality of functionally identical locations onto which the various switching modules can be placed;