Charging a Car Battery – What You Need to Know

No one likes dealing with a dead car battery, especially if you’re stranded away from home. A dead battery means you won’t be able to start your car. And we all recognize the chugging sound of an engine that can’t turn over. That’s why it’s so important to know about charging a car battery. Not only how to do it, but what the risks associated with it are.

What causes a dead car battery?

Car batteries can go flat for a number of reasons. The most common reason is due to wasted electricity. This happens when you leave your lights on or leave a door ajar overnight. The car uses the battery to power the lights and security system, so with these things running for extended periods of time your battery will drain its power.

Another common reason for flat car batteries is corrosion. After extended amounts of driving and idle time, the general use of the car battery will lead to corroded connections which should be checked on frequently. Make sure your hookups don’t have any gunk buildup. It is possible to use products such as epsom salt to remove any corrosion or acid buildup.

Of course we all know car batteries can simply go flat when outside in the cold. The low temperature causes the battery to have to work harder to start your car. If it can’t do the job, the battery will only lose more energy as it keeps trying, thus draining the battery.

How many amps is a car battery?

Your average car battery will have an electrical capacity of 48 amps. The measurement is also known as amp hours, which equates amps to time. A battery of 48 amp hours can deliver 1 amp over 48 ours – or two days. If the car battery is working harder, it can deliver 2 amps over 24 hours, 4 amps for 12 hours, and so on.

How many volts is a car battery?

An average car battery will read a voltage of 12.4-12.9 volts. Your car’s electronic display should show the voltage of your car battery, but you can also use a handheld electrical reader to check the voltage. Any readings below the 12 volt threshold means the car’s battery is not up to full speed.

How long does it take to charge a car battery?

If you’re reading this in preparation to charge your car battery, it’s a good thing to know just how long it will take. It’s not worth getting the process started if you won’t be able to finish the job. When your car’s battery is being charged, you need to supervise the entire process. Since there are powerful electrical forces travelling through the car, mistakes or oversights could lead to injury or damage to the car.

Depending on how much power it has, charging a car battery can take between one hour to one day. Using a 12-volt charger on a 48 amp car battery will take about half a day to charge.

A car battery can also be recharged while driving thanks to the alternator. If your car is idle and you’re charging using a charger, make sure not to keep other electrical components in the car running to save energy. So keep the lights off and doors closed for the quickest charge.