How to Boost a Car Battery Safely

Everyone has been in that situation where you have left your car light on all night and the engine just won't start, which is why it is important to be able to boost a car battery safely and at a minimum risk to yourself and others.

The most important thing to remember when trying to boost a car battery safely is to connect the black (ground) jumper cable to the metal sheath of the dead vehicle rather than the negative terminal of the dead battery, this is a very important safety feature as otherwise it is possible for a spark from the connecting cable to ignite gas emitted from the battery. Another important safety issue is to never let the two clamps of the jumper leads touch each other as this will result in a flurry of dangerous sparks.

With the live vehicle

The first step to boost a car battery safely is to pull the running vehicle alongside the dead one. The vehicles have to be close enough for the jumper cables to be attached correctly with no over stretching. Remove the booster cables and make sure the ends never touch. Take one end of the cables and attach them to the battery under the hood of the running vehicle. Remember there are two posts on a battery with one being positive (usually bigger, red in color, and with a plus sign) and the other negative (black in color with a minus sign). Clamp the red jumper lead to the positive battery post and the black cable to the negative one on the running vehicle making sure the ends do not touch each other.

With the dead vehicle

Working with the dead vehicle and the other end of the booster cables follow the same procedure except clamp the black negative end to a grounded piece of the inner metal sheath instead of the negative post. It is important to attach the red lead first. Both ends of the jumper cables should now be attached to each vehicle.
The next step in how to boost a car battery safely is to tun on the working vehicle for a couple of minutes then try to start the dead car. If the dead battery does not start right away you may need to let it build charge for a couple of extra minutes then try again. Once the vehicle with the dead battery is running do not turn it off as you are recharging the battery by keeping it on.
Finally remove the booster cables starting with the black lead first followed by the red again making sure the end of the cables do not touch each other to avoid sparks. Once safely removed wrap up the jumper cables and store them away to boost a car battery safely another day.