Your car's battery is essential because it enables your engine to start at all. The battery feeds the vehicle's starter by bringing an electrical current that powers the engine. If the battery is running low, the vehicle may be slow to start. If the car's battery dies completely, the engine won't start and you won't be able to go anywhere. To avoid getting stranded, maintaining your car battery's lifespan is key.
Below, you'll learn how long a car battery lasts, the main factors that affect a car battery's lifespan and the warning signs of a damaged car battery. With that in mind, you can then know how to make the most of your car battery's lifespan and what to do when your car battery dies. Whether you're a frequent driver or wondering how long a car battery lasts without driving at all, we'll help you figure out the best way to care for your vehicle.
How Long Does a Car Battery Last?
Car batteries gradually deteriorate until they're no longer able to produce enough power to start the engine. Once a car battery becomes too weak or damaged to start the engine, the battery will need to be replaced. While it typically takes about three to five years for a vehicle's battery to reach this point, the exact car battery's lifespan depends on multiple variables.
Time plays a large role in the rate a car battery ages and how much longer it will last. But other factors affect your car battery's lifespan that you have a bit more control over.
10 Factors That Affect Your Car Battery's Lifespan
These are the top 10 variables that affect how long a car battery lasts:
1. Size of the Battery
Small batteries typically have lower cranking amps, also known as reserve capacity, which is the measure of the total instant power a battery can put out. If a battery doesn't have adequate reserve capacity, it'll have a shorter lifespan. But a larger, more powerful battery does not automatically lead to a longer battery life. It's best to install the battery size that perfectly fits your car's engine.
2. Extreme Temperatures
Whether you live in a hot or cold climate, the weather can affect the lifespan of your car battery. While heat is what sparks the chemical reaction car batteries rely on to generate electricity, it also increases the rate of battery degradation. In hot locations, a car battery may need to be replaced every three years due to the excessive heat.
Colder temperatures can slow down the chemical reactions that deliver power to your car's battery. A colder climate can lead to more frequent cold engine starts that can seriously damage the car's battery over time. In particular, lead batteries do not perform as well in cold environments.
3. Overusing the Electric Accessories
Leaving your vehicle's electric accessories, like the lights or radio, on while parking draws the battery more quickly than usual. Turning these accessories off when you're idling can help preserve your car battery's life.
4. Electrical Problems
Electrical issues like faulty electrical wirings or loose ground straps can make your car's battery discharge. These electrical problems can result in unwanted fires, so you should take your vehicle in for regular maintenance check-ups.
5. Malfunctioning Charging System
A malfunctioning charging system can decrease battery life because persistent over- or under-charging speeds up battery aging. If the battery keeps draining, it could run out of power completely, causing the car to stall. Even if you can recharge your car's battery and put it back in service, letting the battery go completely dead will significantly reduce its lifespan.
6. Short Trips
Frequent short trips can damage your car's battery because they don't allow enough time for the battery to properly warm up and get recharged. Over time, repetitive short trips can harm the car's battery and lead to failure.
7. Cold Starts
Your car needs more electric power to start when its engine is cold. With some assistance from the alternator, the car's battery can still be recharged in just a couple of minutes. But these cold starts will take more and more of a toll on the battery as it ages.
8. Faulty Alternator Diode
An alternator with a poor or faulty diode can reduce battery performance. Ideally, a diode makes the current flow in one direction, but a malfunctioning diode will make the current flow in the opposite direction. The diode may keep the charging circuit working even when the car engine is shut off, which causes drainage in the car battery.
9. Heavy Traffic
Heavy traffic wears on your car's battery for these reasons:
- Keeping the engine running in traffic causes hotter engine bay conditions.
- The slower speed of the engine in stop-and-go traffic decreases the alternator's speed, which limits the charging.
- Most people use car accessories like the radio, heat or air conditioning while sitting in traffic, which wears on the battery.
10. Moisture and Corrosion
Moisture in the engine bay can cause electric shorts, which leads to corrosion forming on some battery terminals and electrical connectors. Buildups of dirt and grease can also cause corrosion. When corrosion occurs, there may be more electric shorts and increased resistance as the flow of the current gets reduced. These issues quickly drain the car's battery.
Signs of a Weak Car Battery
Because your car's battery is essential to keeping the vehicle running properly, be on the lookout for signs of a damaged or weakened car battery to avoid an emergency. Fortunately, there are plenty of symptoms of a weak car battery that can help you fix an issue before it grows into a larger problem.
Watch out for these signs that your car's battery may be fading fast:
- Check engine light: Typically, the check engine light turns on when your car battery's power is weak. Take this as a sign to have your car battery checked out and potentially replaced.
- Dim headlights: A failing car battery cannot fully power the vehicle's electrical components, which include your headlights. If you notice your headlights seem weaker than normal or start to dim as you come to a stop, your car battery may be close to giving out.
- Slow engine crank: When you attempt to start your car, pay attention to whether the cranking of the engine is sluggish. If your key is in the ignition but the motor doesn't turn on or the power tends to falter within about five minutes, look into getting a new battery.
- Clicking noise when you turn the key: Another sign of a dying car battery when you start your vehicle is a clicking sound as the key turns. Turning the key in the ignition prompts the car battery to send a current to an electrical component known as the starter solenoid, which gets the car going. A failing battery will struggle with this function, and the electrical current it sends will be weaker. When a starter receives insufficient power from the battery, it often makes a clicking sound.
- Needing to press the gas pedal to start: You should not have to give your car gas to get it started. If your car will only start properly when you press your foot on the gas pedal, its battery may be failing.
- Low battery fluid level: Many car batteries have a translucent section of the casing, allowing you to keep an eye on the battery's fluid level. If this level drops below the lead plates inside, it may be time for you to get the battery and charging system tested.
- Swollen battery case: A swelling or bloating battery case is a clear sign your car's battery could be dying. Excessive heat can result in a swollen battery case, which decreases the life of the car battery inside.
- Battery leak: A leaking battery will cause corrosion around the posts, which is where the cable connections are located. This corrosion may have to be removed for your car to be able to start.
- Backfiring: When a car battery begins to fail, it can cause intermittent sparks that result in fuel building up in the cylinders. This accumulated fuel can get ignited suddenly and with increased force, making your car backfire. Because backfiring can be a sign of several different issues, you will need to do a battery test to determine whether the car's battery is the source of the problem.
- Old age: A car battery can last for a considerably long time. But it's wise to have the condition of your car's battery inspected by a professional service on an annual basis after it hits the three-year mark.
7 Tips for Extending Your Car Battery Lifespan
You can make the most of your car battery's lifespan by properly caring for it. There are many steps you can take to ensure you aren't unnecessarily draining your car's battery in any way. To maximize the life of your car battery, start putting these seven tips into practice:
1. Limit Short Trips
Because quick car rides prevent the vehicle's battery from fully charging, limiting the number of short rides you take can help preserve its battery life. But you shouldn't skip driving your car altogether to avoid taking short trips. A car can sit for only about a month before the battery dies.
If you have to take frequent short trips or do not use your car often, you may want to purchase a portable AAA battery tender to help keep your car battery fully charged and optimize its service life.
2. Use Hold-Down Hardware to Fasten Your Battery
If your car's battery is not securely fastened, it could vibrate, which often leads to internal damage and short circuits. To minimize the effects of vibration, use special hold-down hardware that secures the battery in place to keep it from moving. Missing or loose hold-down hardware can shorten your car battery's lifespan.
3. Keep Corrosion Under Control
Over time, car battery terminals corrode. But keeping them clear of buildup can help extend the battery's life. To clean your car battery, use a toothbrush dipped in a water and baking soda mixture to scrub the terminals. Then use a spray bottle to spritz the area with cold water and rinse the mixture off before following up with a thorough drying.
4. Don't Use Electronics While Idling
Frequent extended periods of idling can harm a car's battery. To avoid putting extra wear and tear on your car battery, turn off functions like the air conditioner or the radio when the engine is not running. Charging your phone in the car can also damage the battery over time.
5. Turn Off All Your Lights After Exiting
Accidentally leaving your headlights or car door lights on after exiting the vehicle can put excess strain on your car's battery. If you often forget to turn off your vehicle's lights as you leave, consider posting a note on your dashboard to remind yourself. You could also park in a direction that forces you to walk past your headlights on your way to your destination.
6. Test Your Car Battery Regularly
If you want to maximize the life of your car battery, you need to know what condition it's in. You can test your car battery's output voltage level by using a tester or going to an auto repair center. Assessing your car battery on a regular basis will tell you how well you're maintaining it and whether you'll need a new one soon.
7. Take Care of Your Whole Car
A vehicle is made up of numerous parts working together. Routinely taking your car in for an inspection of all its parts is one of the easiest ways to ensure your car battery's lifespan reaches its full capacity. Properly maintaining all your vehicle's parts will also extend the life of your vehicle as a whole.
AAA Car Battery Services
No matter how well you look after your car's battery, you can't always predict when it's most likely to die. Being unable to start your vehicle due to an uncharged car battery can be inconvenient or even a safety hazard. If your car battery unexpectedly gives out, roadside assistance from AAA can help you get out of an emergency.
If you're a AAA member and experience car battery troubles, you can receive these helpful AAA services:
- Car battery and charging system testing: AAA roadside assistance can test your car battery and charging system and replace them if necessary. If you're located in a covered area and qualify, this on-the-spot service will come to you for no charge.
- AAA batteries: If AAA batteries are right for your vehicle's make and model, they're a dependable choice because they are engineered to withstand any climate. Those who qualify will also enjoy a three-year warranty.
- Savings: When a AAA member buys a AAA battery, they save on the already competitive AAA car battery prices.
- Delivery and installation: For most vehicles, AAA will deliver and install the new car battery for free.
- Old car battery removal: When you choose to have a new AAA battery installed, AAA recycles and disposes of your old car battery for you.
Start by getting an instant battery quote from AAA today.
Browse the AAA Blog for More Useful Resources
At AAA, we believe needing a car battery shouldn't ruin a trip. Get back on the road as fast as possible with a AAA membership, which includes a variety of car battery and roadside services. With a AAA membership, you can drive with confidence knowing our roadside assistance is only one call away.
For additional resources about car battery maintenance, check out our AAA blog. To find out which services are offered in your area, contact your local AAA office.
