Assembly for a vehicle, said vehicle comprising: - an electrical battery having a first terminal (VBAT) and a second terminal (-VBAT), - an electrical energy storage element, one terminal of which is linked to the first terminal (VBAT) of the battery and the other terminal of which is linked to an electrical ground, said assembly comprising: - a first circuit, capable of consuming electricity coming from the electrical battery, and having a first and a second terminal connectable to the first and second terminals (-VBAT, VBAT) of the electrical battery, respectively, - electrical power supply management means comprising a first transistor, said means being configured to allow or prevent the passage of electrical current between said electrical energy storage element and said first circuit, said assembly also comprising a second circuit connected to the storage element so as to be able to be powered by said storage element, - a controlling device comprising: • detection means configured to detect a drop in the voltage of the electrical battery below a threshold value; • command means configured, in the case of detection of a drop in the voltage of the battery below said threshold value, to command said electrical power supply management means to prevent the passage of electrical current between the electrical energy storage element and said first circuit, the second circuit comprising the command means, and the second circuit being configured to be able to be powered by the electrical energy storage element in the off-state of said first transistor. - an electrical battery having a first terminal (VBAT) and a second terminal (-VBAT), - an electrical energy storage element, one terminal of which is linked to the first terminal (VBAT) of the battery and the other terminal of which is linked to an electrical ground, said assembly comprising: - a first circuit, capable of consuming electricity coming from the electrical battery, and having a first and a second terminal connectable to the first and second terminals (-VBAT, VBAT) of the electrical battery, respectively, - electrical power supply management means comprising a first transistor, said means being configured to allow or prevent the passage of electrical current between said electrical energy storage element and said first circuit, - a first circuit, capable of consuming electricity coming from the electrical battery, and having a first and a second terminal connectable to the first and second terminals (-VBAT, VBAT) of the electrical battery, respectively, - electrical power supply management means comprising a first transistor, said means being configured to allow or prevent the passage of electrical current between said electrical energy storage element and said first circuit, said assembly also comprising a second circuit connected to the storage element so as to be able to be powered by said storage element, - a controlling device comprising: • detection means configured to detect a drop in the voltage of the electrical battery below a threshold value; • command means configured, in the case of detection of a drop in the voltage of the battery below said threshold value, to command said electrical power supply management means to prevent the passage of electrical current between the electrical energy storage element and said first circuit, - a controlling device comprising: • detection means configured to detect a drop in the voltage of the electrical battery below a threshold value; • command means configured, in the case of detection of a drop in the voltage of the battery below said threshold value, to command said electrical power supply management means to prevent the passage of electrical current between the electrical energy storage element and said first circuit, • detection means configured to detect a drop in the voltage of the electrical battery below a threshold value; • command means configured, in the case of detection of a drop in the voltage of the battery below said threshold value, to command said electrical power supply management means to prevent the passage of electrical current between the electrical energy storage element and said first circuit, the second circuit comprising the command means, and the second circuit being configured to be able to be powered by the electrical energy storage element in the off-state of said first transistor.