Abstract: A mechanical latch relay started by a current pulse is disclosed which comprises an electromagnetic generating unit, a connecting mechanism and a mechanical locking mechanism, and which can maintain the existing operation state when the current pulse starting the relay disappears, and it changes its operation state when another current pulse is provided, and then it keeps the operation state even if the pulse disappears so that it can provide a stable operation state of current on/off unnecessary to be provided with a current for a long time, which enables to provide an effective control for current on/off.

Abstract: In 3-pole vehicle batteries with a cranking battery (2) and an auxiliaries battery (8) a device accompanies the battery wherein a switch R1 connects and disconnects the like poles (6,12) so that may receive charge and a switch R2 which connects and disconnects electrical auxiliaries to and from the auxiliary battery. The device senses the state of charge of the auxiliary battery and the current flowing from the auxiliaries battery to the cranking battery. A microprocessor .mu.P uses this and extra data to open R2 and prevent any serious discharge of the auxiliaries battery; to close R1 to permit charging of the cranking battery and to allow the cranking battery to assist a partially discharged auxiliaries battery; to open R1 when overcharge is indicated. In a second version only switch R1 is present but a detector senses the operator's requirement to start the vehicle and closes R1 to join the outputs of the cranking and auxiliaries batteries.

Abstract: The present invention provides a switch for a battery charging system for a motorized vehicle including a starter motor, a battery with a CRA part and an AUX part, and a battery charging generator wherein the switch includes a series connector between the CRA and AUX parts and a sensor which senses at least a state of charge of the CRA part and prioritizes the generator current to the CRA part through the series connector.