Is Your Car Battery Healthy?


   Car batteries are one of the most important aspects of a car as it powers all the electrical parts found in your vehicle. It has to make the car start, run the air conditioner, play music, operate windshield wipers, and switch on headlights at night.

You may face difficulty starting your car in the morning or encounter dim lights at night if your battery does not have enough power.

While a typical car battery lasts four to five years, it ultimately depends on how much you're using your car and how. Let’s take a look at certain things, which determine whether your car battery is healthy or not. 

Check the Voltage

In order to determine voltage in various devices, one can use a voltmeter, which can be either an analog or digital one, depending on personal preference and affordability.

Begin by turning off all devices that may draw their power from the vehicle’s battery, such as ignition and radio, among other things. 

Remove the covers from the posts of the battery. Attach the positive lead of the voltmeter to the red post and the negative lead to the black post. Check readings—a health battery should display anything between 12.4V and 12.7V.

For instance, anything about 12.5 V shows that your battery is in good condition, while around 12.3 V indicates that the battery is charged up to 75%. Anything below 11.8 V means that your battery is low, and hence it is working with less than a quarter capacity.

However, these are only assumptions, as accurate results can only be produced when testing the battery under load rather than just relying on voltage readings.

Headlights Test

Incidentally, if you lack a voltmeter, the behavior of your headlight when starting the vehicle can give you an idea of how well your car battery is doing health-wise.

Turn on the headlights and observe their brightness. In case they seem to be dimmer than usual, this implies low charge in your battery.

On the other hand, if at startup, headlights brighten up, it shows that the alternator is doing its job but not supplying enough current for the complete charging of the battery.

If there is no change in headlight brightness when starting the car, then your battery may be working fine. 

Battery health indicator

Modern vehicles are equipped with a battery health indicator, which is just a small device attached to the battery itself. When you switch on the ignition key, an arrow painted either red or green starts moving accordingly.

The red color indicates that voltage is low within a battery, while green means that it is alive and kicking! If the arrow is black, it could very well mean that your battery is dead and drained empty.

Load Testing and Power Probing

For a comprehensive assessment, use a car battery tester that has a CCA rate. Likewise, if your voltmeter isn't in place, opt to employ the power probe on the positive terminal of the battery and the negative tip on the negative pole.

A healthy battery should give a reading between 12.2 and 12.9 volts. Remember to switch off the ignition as well as all other accessories depending on the battery for accurate results. Testing under load is more reliable than just measuring voltage.

Monitoring charge flow into and out of a battery using an ammeter helps assess its charging performance. This will help establish if your alternator charges it completely or not. If incoming charge equals expected capacity, your battery is most likely in good shape.


Hydrometer Check

A hydrometer is a device that determines the amount of acid in a battery’s electrolyte and shows its state. It is advisable to use a hydrometer having an inbuilt thermometer for correct results. Other models are self-adjusting, while some require you to consult the conversion table.

Take into account that battery acid is dangerous, and therefore one should always put on gloves if they are wearing them. You should not use a metallic thermometer as it reacts with the acid.

First, open the cell covers of the battery before doing this test. Put the first cell into which you have inserted a hydrometer, then squeeze its bulb to allow electrolyte to get drawn into it. Then take off this liquid back into the same container after observing its specific gravity reading.

The same process should be repeated for each of these cells. A normal battery will read between 1.265 and 1.299 in terms of specific gravity. Low readings indicate undercharging, while large differences between cells show sulfation processes.

Physical Inspection of the Battery

A physical examination of the car battery is necessary to detect any cracks. To do this, you first need to disconnect the battery terminals and then take out the battery from the car.

Put the battery on a flat surface and examine its surface for no bulges. Doming of the battery occurs when it is overcharged. Lastly, inspecting the insulation of the terminals will lead you to see if there are any cracks in them.

Before putting the battery into its carrier, make sure you clean it up. Cleaning of batteries is simple. You just need some baking soda solution, water, and a soft brush.

Pour all these together into a container and wash gently with your soft brush around the top and sides of your battery, after which you can use a dry cloth to wipe off excess liquid.

Check to find out whether there is any corrosion on your battery carrier and ensure that all screws are in their place firmly enough. After cleaning it properly, put it in its carriage, taking care not to let it sway leisurely before screwing it up again securely.

Finally, change the positive terminal followed by the negative one before closing anything, including the cover. Vaseline can also be applied to poles so as not to corrode them again while covering.

Frequently Asked Questions

●How long does a car battery typically last?

A typical car battery lasts around four to five years, depending on usage patterns and maintenance.

●What voltage range indicates a healthy car battery?

A healthy car battery should show voltage readings between 12.4V and 12.7V when tested with a voltmeter.

●How can I check my car battery's health without a voltmeter?

Observing your headlights' brightness during startup can indicate your battery's health; dim headlights may signal low battery charge.

●What does a battery health indicator show?

A battery health indicator, often colored red, green, or black, reflects battery condition: green for good, red for low voltage, and black for dead battery.

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