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How Long Do Car Batteries Last? | 6 Signs Of A Weak Battery

The frustration that follows turning your ignition with no response is inexplainable. Even worse when you are in a rush. A dead battery can be the cause of your frustration. It renders your vehicle unusable and leaves you stranded. So, contrary to popular beliefs that some vehicle components are more important than others, all components are important. Knowing how long a car battery is expected to last and signs of a dying battery would help prevent your battery from giving in unexpectedly. Keep reading, and we will explain everything you need to know about car batteries, including how long they are expected to last.


How Long Do Car Batteries Last?

Car batteries usually last between three to four years. However, a battery’s lifespan could be greatly affected by climate conditions and driving habits. If you reside in a warmer climate, you may need a battery replacement sooner than someone living in a colder climate. The higher temperature evaporates the battery fluid and has a more damaging effect on your battery. Repeated short trips also impact the longevity because it doesn’t give the battery enough time to recharge after the strenuous task of powering the engine. 

Regardless of climate conditions and driving habits, all batteries eventually wear out and stop holding a charge. The most apparent symptom of your battery going downhill is that your car struggles when starting. However, you first want to inspect your battery connections to ensure that they are tight and there are no broken or disconnected wires before concluding that you need a new battery. 

A good rule of thumb is always to have your battery inspected during every oil change after three years of use. You want to ensure that the battery is properly secured, free of corrosion, cracks, or fluid leaks, and it holds a charge. You should always test the alternator to ensure that it is not under or overcharging the battery whenever you get a battery replacement.

6 Signs Of A Dying Car Battery

The good news about a degrading battery is that they usually give some warning signs as they begin to weaken. While these symptoms may sometimes signify irredeemable battery damage, other times, it could be a minor issue that can be easily rectified. However, how fast you respond to the symptom could determine whether your battery lives or dies. The following are symptoms of a dying battery:

#1. Slow Cranking

Over time, the active materials in the battery plates deteriorate from the expansion and contraction during discharge and charging cycles. When this begins to happen, the capacity of your battery to hold a charge and sufficiently supply power to the starter motor is impacted. You may notice that your engine cranks for longer, and it takes some seconds before the engine starts.

#2. Dim Lights

The battery provides energy to power your vehicle’s electrical system by converting chemical energy into electrical energy. When the battery degrades with age, the ability to power electrical components reduces. You may notice that your headlights aren’t as bright as they used to be, and the interior lights are dimmer. This indicates that you need battery service before it breaks down unexpectedly.

#3. Leaking Or Corroded Terminals

Leaks and corrosion are the most apparent symptoms of a degrading battery. The major causes of battery leaks include an old, damaged, or overcharged battery. Oftentimes, battery leaks usually lead to corrosion. The compromised structural integrity of an old or damaged battery makes it prone to leaks.

Corroded battery terminals do not instantly damage the battery but could destroy it with time if left unaddressed. A faulty alternator could overcharge your battery, causing the release of electrolyte vapors from the vent cap. The reaction between the acidic steam and your battery metal parts causes corrosion. When you notice leaks or corrosion on your battery, it is an indication that you need to get your battery checked.

#4. Bad Smell

Another symptom of a dying battery is the release of an awful smell. When your battery heats up from overcharging, it converts the sulphuric acid into hydrogen sulfide, which is the cause of the awful rotten-egg smell. The pungent smell is mostly a sign that your battery is overcharging or leaking. You may want to consider a car battery replacement because you don’t want to get stranded with no assistance or jumper cables in sight.

#5. Malformed Shape

Overcharging a battery expands the cell plates and causes the buildup of hydrogen gases faster than the battery can disperse. This, in turn, causes the battery case to swell. Excessive heat can also cause your battery to swell. If you notice your battery is deformed or swollen, it is an indication that your car battery lifespan is declining.

#6. Warning Lights

When there is an issue with the battery, your car will notify you by activating the battery warning indicator on the dashboard. A failed battery could also trigger the check engine light. However, before getting a new car battery, you want to check that a damaged battery indeed triggered the dashboard light because a failing alternator could also be the culprit. 

Whenever you notice any of the following symptoms, it is an indication that your battery is due for replacement. Ignoring these signs could result in your battery’s unexpected failure, leaving you stranded.


Factors That Affect Your Battery’s Lifespan

Despite regular car maintenance, a battery will begin to degrade after an extended period of use. However, a few factors could significantly accelerate your battery deterioration, reducing battery power and causing it to fail sooner than expected. These factors include:

— Driving Habits

Apart from the familiar tip that you shouldn’t use your infotainment or air conditioning system without your engine running, some other habits could significantly shorten your battery’s longevity. Frequent short commutes or parking your vehicle for long with the battery unused could affect the life of your battery. Batteries naturally self-discharge and lose a huge charge after every ignition cycle. They only get sufficiently recharged when the engine is running. Parking your vehicle for long and continuous short commutes doesn’t allow them to recharge.

— Climate

Extreme temperatures also affect batteries. While cold temperature impacts their performance, hot temperature shortens their lifespan. The boiling temperature accelerates the chemical reaction speed, which in turn increases the battery output. The downside of an increased chemical reaction is that it hastens the rate of battery degradation, thereby reducing its longevity.

— Proper Battery Hardware

Your battery is only as good as its capacity. Using a battery with a different output from your manufacturer’s recommendation will always cause issues. If the battery is too big, it would damage your alternator and won’t last if it is undersized. Undersized batteries won’t hold enough charge to power your vehicle and would die out often. The continuous deep discharge and recharge cycle would impact its lifespan. So, you want to ensure you get the right size.

Tips For Extending Your Battery Life

Although a battery is expected to last up to four years, some factors can significantly expedite its depreciation, causing you to need a new one within a year or two. So, how do you get the most out of your car battery? Here are some tips to extend your battery life. 

Minimize the use of electrical components while the engine is off. In the absence of engine power, the battery provides power to all the electrical components. The use of the battery charge for a long period of time without recharging would lead to deep discharge. Repeated deep discharge and recharge cycles accelerate battery failure.

Disconnect the terminal or invest in a trickle or battery charger to prevent the battery from discharging if your vehicle isn’t started or driven very often. You also want to avoid frequent short-distance commutes. Batteries lose considerable charge to get the engine started, and short trips don’t usually leave enough room to recharge. Hence, if you often embark on short trips, you may want to consider going on a road trip to allow your battery to recharge fully.

A battery needs to be regularly inspected for wear signs once it exceeds three years. Look out for leaks or corrosion and ensure that the battery is free of vibrations by fastening it with a clamp. You should also load test the battery on every maintenance visit after three years of use.

Test the alternator to ensure it is not under or overcharging the battery whenever you replace your battery. Some vehicle models, especially BMWs, also require the registration of new batteries for optimal charging and performance.


The Bottom Line

Your vehicle’s battery only lasts so long — besides normal wear and tear, other factors, including driving habits, battery capacity, and weather conditions, could hasten its deterioration. The average car battery lasts between three to four years but should be closely monitored after three years of use to avoid unexpected failure.

Frequently Asked Questions

Should I replace my car battery before it dies?

Yes, you should. Turning on the ignition without your car starting can be quite a frustrating experience. This is what you get most times waiting until your battery dies. You don’t have to leave the battery until it eventually dies before getting a replacement. Batteries usually show some telltale signs once they begin to decline. Whenever you notice any of these symptoms, it is best to get a replacement. A general rule is to consider replacing your battery once it exceeds three years.

How long do you usually have to wait before your car battery is fully charged?

The charging time usually depends on the age and condition of the battery, the charger’s output, and battery capacity. The most common way of recharging your battery is through the alternator or with a battery charger. Recharging your battery with the alternator after a deep discharge could take up to six hours.

However, it is best to charge your battery after a deep discharge with a charger instead of the alternator. The alternator has a high charge rate designed to recharge the battery after starting or short discharge. Batteries are best charged at slower rates after deep discharge, usually below ten amps over 8 to 12 hours or even more.

How often should you check your car battery?

It is recommended that you inspect and test the life of a car battery regularly. You should check that there are no cracks, leaks, or corrosion and that the terminals are properly connected. A battery needs to be closely monitored and tested during every service appointment after three years of use. You want to have the battery and the charging system tested to ensure they are properly working.

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