Abstract: The subject invention is about a portable battery jump starting device for stranded vehicle due to weaken starting battery. It is equipped with a pair of power cable connected to crocodile clips. The internal circuit of the subject invention is capable of detecting polarity at the point of connection to the external battery and is capable of compensating a wrong polarity connection. The subject invention offers automatic power on/off and a will guarantee a correction connection at any circumstance. Therefore it eliminates the risk of battery explosion due to human error.

Abstract: An apparatus that can be used to jump-start a car that has a weak battery. It includes a battery booster pack or a battery booster cable that is polarity sensitive and can detect proper and improper connections before providing path for electric current. This apparatus eliminates the danger of reverse connections, shorts, fires, spark firing and battery explosion. The apparatus requires no separate switching mechanism to turn power on or power off. It also does not require the imperfect human judgment of any indication device to determine correct or incorrect connection. The clamps detect for the correct polarity and automatically control the power. Power turns on once a good connection has been made. If user makes a wrong connection, there will be no power but its warning signal will go off. Once a clamp is dislodged from the battery terminal, it automatically turns power off without the need to deactivate a switch.