Abstract: A charger device is configured with electric conducting devices corresponding to electric conducting contact points of a battery. The electric conducting contact points are correspondingly associated with the charger device, a detector device and an automatic switching device. When the charger device is connected to the battery, the detector device determines size of charge current, and when the detector device determines that the charge current has not reached a set value, then the automatic switching device switches a normal charge mode to a boosting charge mode. The detector device stops the charger device from charging if the battery has already been charged for a predetermined time but has not reached a set value, and a display device displays that an abnormal state has occurred, thereby enabling the charger device to achieve the objective of providing good charging effectiveness and functionality to detect abnormalities when connecting to a battery.

Abstract: The present invention provides a device for automatic detection of battery polarity, wherein a detector circuit is structured from detector terminals, detector units, positive voltage electrical connecting units and negative voltage electrical connecting units. Operational procedure involves first connecting battery electrical conducting units with the detector terminals of the detector circuit, when the detector terminals are connected to positive poles of the battery, then one set or more than one set of the detector units of the detector circuit detect positive voltage, which actuate an electrical connection with the positive voltage electrical connecting units, thus connecting positive poles of the detector device to the detector terminals and connecting to positive poles of the battery, at the same one set or more than one set of the detector units determine negative voltage and actuate a connection with the negative voltage electrical connecting units, thereby forming a complete circuit.

Abstract: The present invention provides an improved structure for a battery plug, wherein plug contacts are plugged into a plug socket to supply electric power, which is conducted to conducting wires. Magnets serve as electrical connecting interfaces when the conducting wires are connected to positive and negative poles and electrical contact points of a battery, Moreover, the magnets are each provided with a strong attraction function which is used to prevent the conducting wires from separating from the positive and negative poles of the battery and producing poor contact with electrical contact points of the battery. Furthermore, the magnetic magnets can be freely moved, and are not affected by shape or size of the battery or different positions and spacings of the contact points, thereby enabling the plug device to achieve multifarious electrical connecting functionality, and provides the plug device with increased originality and practicability.