How to Charge a Car Battery


Every organism or mechanism has a part that makes it work. With humans, that part is the heart, but when it comes to cars, that part is the battery. So one can say the battery is the heart of a car.

A battery is so crucial for a car’s movement that most people would rather have a leaking radiator or engine than have a faulty battery. A defective or dead battery is one of the worst things to happen to any car; it pretty much turns the car into a shaded bench.

A dead battery can be prevented or fixed by frequent charging. Typically, the lifespan of a car battery is between three to five years. Unfortunately, extreme weather conditions and little mistakes like leaving your headlights on in the day can cause the battery’s lifespan to shorten or die.

To get your battery working again, you can easily take it to a mechanic and ask for a battery check-up. The check-up usually consists of a check on the temperature at which your battery may fail.

If you are sure the problem with your battery is that it is low in charge, you can skip all the unnecessary money spending and recharge it yourself.

How a Car Battery Works

To charge a car battery, first, you must understand how it works.

Batteries have three basic components: Anode, Cathode, and Electrolyte. Discharging electricity releases electrons from the anode. These electrons later find their way to the negatively charged terminal of the battery. The name of this process is oxidation reaction because not only are electrons released, ions get released too.

On the other hand, the positive terminal has the cathode, which is in charge of receiving electrons. At the same time, the electrolyte is responsible for creating a balance between the two terminals by preventing the electrons from going directly from the anode to the cathode.

Without an electrolyte controlling the releasing and accepting process, the completion of the battery’s circuit is not possible. An incomplete circuit means that the creation of chemical energy is also impossible.

How to Charge a Car Battery

Before hooking up a car battery for charging, you must prepare appropriately for it. It is not hard to get electrocuted by a battery; all it takes is one or two mistakes. For safety and health reasons, always ensure you have the necessary tools for the job, and always remember to wear gloves.

To begin, turn off all accessories in the car, from the ignition to the interior lights. Pull out the negative cable; it is the black one. If your cable colors may have undergone some changes during one of your trips to the mechanic, you can check the top of your battery to find which is the negative cable. It is the cable with a negative sign (-) on it.

After removing the cable, clean your terminals with a water and baking soda mixture. The baking soda mixture helps in neutralizing the battery’s acid. It is advisable to use a brush instead of a cloth for this.

Protect your face with goggles and a mask before cleaning the terminal, as a considerable amount of acid buildup can produce airborne corrosion which can cause severe damages to your nose, eyes and mouth. It’s best not to touch your face until you wash your hands for safety reasons.

If your battery has removable caps, open them up and check the battery’s water content. Refill with only distilled water if the water level is low. Recently, battery designs are “maintenance-free” so you might not be able to open yours up to check its acid level.

The next step to follow is the charger instruction step. Always follow the instructions particular to your charger.

Most chargers have similar instructions, with only slight changes. Below are basic instructions of battery chargers:

  1. Turn off the charger.
  2. Connect the positive cable to the battery’s positive terminal.
  3. Connect the negative cable to the battery’s negative terminal.
  4. Reduce the charging rate to its lowest option.
  5. Turn the charger back on and set a timer.
  6. Turn the charger off and remove the negative and positive cables.

Do not over-charge your battery. The time needed to charge a battery properly totally depends on the open-circuit voltage and the number of amps on the cold-cranks.

For below 11.58 battery voltage, your charger should put out a 5-amp charge rate, especially if you are using 500 to 400 cold-cranking amps. Charging should take about twelve hours if these are the conditions in which you operate.

Different Types of Car Battery

Car batteries come in various sizes, but they all play crucial roles in the smooth running of any car. When choosing a new battery, you should always consider voltage, current, CA, and cold-cranking amps for the best choice to be made.

Listed below are two types of batteries; Lithium-ion (Li-ion), and Lead-acid.

Lithium-ion Battery

The Lithium-ion battery has recently become popular in the automobile industry. This popularity stems from the fact that hybrid and electric cars make use of Lithium-ion batteries because they pack more charges than their counterparts. Lithium is a light metal; this property allows for a more lightweight battery that still retains excellent charging abilities.

Lead-acid Battery

Invented by a French physicist called Gaston Planté in 1859, the lead-acid battery was the first type of rechargeable battery made for commercial use.

As its name suggests, the lead-acid battery makes use of sponge or peroxide lead for the conversion of chemical energy to electrical energy. Due to its high cell voltage feature and affordability, lead-acid battery has been able to stand the test of time.

Battery terminal, separators, active material (lead), plate and container are the parts of a lead-based battery that work together to enable the lead-acid battery compete against its rivals in the automobile industry.

When Your Battery Might Need Charging

  • Leaving your headlights on might be one of the reasons why your battery keeps dying on you. Designs in newer models of vehicles have a feature which turns off car’s headlights after a certain amount of time has passed. If your car doesn’t possess this feature, always ensure to turn your headlights off to help preserve your battery.
  • Loose connections in your negative and positive cables can prevent your battery from starting. You can quickly fix this by reconnecting your cables properly.
  • During freezing winters and scorching summers, you may notice that your battery drains or even dies quickly. Older car models are more susceptible to this problem, unlike newer models which tend to have more resistance towards intense weather conditions.
  • Sometimes age isn’t just a number, it can also be a problem. Batteries are consumables so it shouldn’t surprise you when they age and weaken in performance.


The average car battery lasts about three to five years tops. When this time expires, do well to replace your car’s battery, or you can follow the steps written above and recharge the battery yourself. Always remember that the hours of charging required depends on your battery’s voltage, cold-cranking amps and current capacity.