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Have You Been Charging Your Dead Car Battery Wrong?

Have You Been Charging Your Dead Car Battery Wrong?

You have probably been a victim of a dead car battery. Perhaps the battery is too old, too worn out and needs changing or perhaps you left the radio and other car electronics on for a prolonged period with the engine off. Whatever the case, you will need to charge that dead battery if you plan on moving your car, and you cannot change the battery.

But how does one go about charging a dead car battery? Do you simply just hook up a charger and begin charging the dead battery? No, there is a correct and a wrong way of doing it. Take, for instance, you need to know which terminal should be disconnected first if you need to remove the battery. There is also a specific terminal that should be connected to the charger first and there is also the recommended time you should charge a dead car battery.

Before we get into how to charge a dead car battery, you first need to know how to take out battery safely if you need to remove it. If the battery still has some little juice, you could easily get yourself shocked. Thus, you need to the proper tools for handling the battery. Different vehicle makes and models have their batteries located at various locations; some are in the trunk, under the fender, under the seat, etc.

Jumping the Dead Car Battery

Ensure all electronics inside the car are turned off including the interior lights. Anything that consumes power might cause the battery to arc while you are still working on it. When you have accessed the battery, you should first remove the negative/ground cable first. This cable is always black in color unless somebody replaced it with the wrong colored cables. It should be attached to the top of the battery with the (-) negative sign.

You will need to clean the battery terminals using a terminal cleaning brush. You can also use a mixture of baking soda and water to neutralize the acid in from the battery. If the terminals and its posts have a lot of acid buildups, you will need to scrap it off, but you must ensure you have covered your eyes, nose, and mouth as some of the scrapping will likely get airborne and are corrosive in nature. You should also not touch your face until you have thoroughly washed your hands.

If you have the old type of battery that comes with removable caps, you can check to see if the water level is too low in any of the cells by carefully prying the caps off. You can top it up using distilled water while taking precaution not to overfill the battery. However, today’s batteries are ‘maintenance-free’ and don’t have an opening for adding water.

Connecting the Battery to the Charger

You should rely on the owner’s manual, but the basic instructions are as follows:

  • First ensure that the charger is off.
  • When connecting the cables, first start by connecting the positive cable on the charge then connect to the battery’s positive terminal.
  • Next, connect the negative cable, then connect it first to the charger then next connect it to the negative terminal of the battery.
  • Set the charger charging rate to the lowest
  • Turn the charger on and set the timer

Before removing the charger, ensure you turn it off first. Next remove the positive cable followed by the negative cable and not the other way round.

For how long should you leave the Battery to Charge?

As to for how long you should leave your battery to charge, it depends on the battery voltage. Say your battery’s voltage is below 11.85, and the charger’s output is 5 Amp, it will take about 12 hours for the battery to charge fully. Had the charger’s output be 10 Amps, it will take 6 hours to charge to full capacity.

However, if the cell is bad, the battery will hardly hold any charge. If this is the case, you will most likely need to change the battery.

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