Everything You Need to Know about Car Batteries (+ Costs)

Car batteries can last for years, but they always seem to die at inconvenient times.

How can you tell if your battery is weak?
And what causes the battery to die?

Don’t worry!
We’ll explore everything you need to know about car batteries, including when to replace an old battery and how much it’ll cost.

Let’s go.

This Article Contains

How Does a Car Battery Work?
How to Find the Right Battery for Your Car
What Are the Different Types of Car Batteries?
6 Signs Your Car Battery Is Weak Or Dead
Is It Safe to Drive with Battery Problems?
How Often Do You Need to Replace Your Car Battery?
How Much Does a Battery Replacement Cost?
6 Factors That Can Shorten Battery Life
What to Do if Your Battery Is Dead?
Are You Sure It’s The Battery?

How Does a Car Battery Work?

Switching on your vehicle’s ignition signals the car battery to start a lead-acid chemical reaction — where ions in the electrolyte solution move between the lead plates. The chemical reaction generates an electric current that’s sent to the battery terminals, which deliver the electrical energy to the starter motor to crank the engine.

The electric potential in your car’s battery is called voltage, and most vehicles use a 12-volt battery. Even a small decrease in the voltage can greatly affect your battery’s performance.

Now, You can’t just use any 12-volt battery. You must choose the right battery products for your car.

How to Find the Right Battery for Your Car

There are four important considerations when choosing the right automotive battery:

Battery type: A lead-acid or absorbed glass mat battery suits most gas-powered vehicles. These aren’t suitable for a hybrid or electric vehicle, which use a nickel-metal hydride or lithium-ion battery.

Battery group size: Batteries are organized into various groups — called the BCI (Battery Council International) group. It covers your battery’s dimensions, voltage, and terminal locations, ensuring it fits into your vehicle’s battery case. You can find the battery group size in your owner’s manual or on the old battery label.

Cold-cranking amps: The CAA or Cold-Cranking Amps measure how much electrical energy a charged battery can provide for 30 seconds at 0°F. The higher the number, the better your battery will perform in cold weather.

Reserve capacity: It tells you how long the battery can power your car without recharging. The higher the reserve capacity, the further you drive when the charging system fails.

Wondering what are the different battery types?
Let’s explore them.

What Are the Different Types of Car Batteries?

Cars may use different types of batteries, including:

Flooded lead-acid battery (FLA battery): The traditional car battery is a flooded lead-acid battery (wet cell battery). They’re commonly used in cars and golf carts.
Enhanced flooded battery (EFB battery): Enhanced flooded batteries are a step above traditional flooded lead-acid batteries. You’ll find an enhanced flooded battery in RVs and some marine vehicles.
Valve-regulated lead–acid battery (VRLA battery): These are relatively maintenance-free compared to lead-acid batteries. A VRLA battery may be an AGM or gel cell battery (both offer deep-cycle battery capabilities):
- Absorbent glass mat battery (AGM battery): These batteries contain glass fiber mats between lead plates that soak up the electrolyte solution, rendering it spill-proof. AGM batteries are useful for vehicles with high battery power demands.
- Gel cell battery: This battery’s electrolyte is suspended in a silica medium, making it spill-proof as well. It’s durable and vibration-resistant, making it ideal for power sports vehicles.
Lithium-ion battery (Li-ion battery): Lithium-ion batteries have a high energy density and can be recharged frequently. They’re commonly used in a hybrid or electric vehicle.
Nickel–metal hydride battery (NiMh battery): These rechargeable batteries also have a high-energy density and can be charged quickly. Nickel-metal hydride batteries are used in hybrid vehicles.

After knowing the types of batteries, let’s see how to tell if your battery is weak.

6 Signs Your Car Battery Is Weak

While a dead battery won’t start the car at all, you can check for these warning signs of a weak battery:

Illuminated check engine light or battery light: Low battery power may cause electrical system issues that alert the Engine Control Unit (ECU) and trigger the check engine light. The low voltage may also trigger the battery light on your dashboard.
Engine cranks slowly or doesn’t turn over: A weak battery won’t have enough power to crank the engine, leaving it sluggish or unable to turn over. You’ll also hear a clicking noise when you turn the key since the starter solenoid fails to engage.
Dim lights and other electronic issues: The headlights may dim or flicker when the battery is weak. You may also notice issues with other electronic accessories, like your radio or power windows.
Swollen battery case: If you see a swollen battery case during a visual inspection, you’ll know it’s time to get your battery checked or replaced. This could be because of overcharging, and the battery will likely fail soon.
Low battery fluid: A conventional battery (lead-acid or flooded batteries) requires periodical battery fluid or distilled water top-ups to convert chemical energy into electricity. If you notice the fluid level is frequently lower than the top of the internal lead plates, it’s probably time to have your battery tested. Such fluid level drops are usually due to evaporation from overcharging.
Rotten egg smell: If you get a rotten egg smell, you’ll need a new battery as soon as possible. The smell is due to a battery acid leak (sulfuric acid) triggered by overcharging, corrosion, or battery wear.

Wondering if it’s fine to drive with a weak battery?
Keep scrolling to find out.

Is It Safe to Drive with Battery Problems?

No, once your vehicle’s battery shows signs of problems, it’ll continue to get worse and could leave you stranded.

Sure, you can jump-start the vehicle to go home. However, if the vehicle stalls, the battery likely won’t have enough juice to restart the engine. This is particularly dangerous if you stall in a high-traffic area, like in the middle of an intersection.

Driving with a weak battery is only recommended if you’re driving straight home, and it’s always best to get a battery replaced before any issues arise.

Next, let’s see how long a standard battery lasts.

How Often Do You Need to Replace Your Car Battery?

Most car batteries last around five years if they’re cared for. However, depending on environmental conditions and driving habits, you could require a car battery replacement in about three years.

That’s why you should test your battery’s health annually once it’s two years old (in warm climates) or 4 years old (in cold climates).

Need to save up for a new car battery?
Read on to get an estimate.

How Much Does a Battery Replacement Cost?

A car battery replacement costs about $360 to $380.

However, this cost can vary depending on your vehicle’s needs, battery type, and mechanic’s labor rate.

Here are new car battery estimates based on type (excluding labor costs):

Lead-acid battery: $185 to $300
AGM battery: $250 to $400
EFB battery: $230 to $270
Deep cycle battery: $130 to $600
Lithium-ion battery: Starts from $950

Next, let’s explore what factors can harm your battery.

6 Factors That Can Shorten Battery Life

Here are some of the most common reasons that can lead to a dead battery:

Time: A car battery degrades after 3 to 5 years of use, depending on your driving habits. This may result in a lower charge capacity and the battery being unable to start the car.
Extended periods of inactivity: If you leave your vehicle unused for long periods (anything over 2 weeks), your car battery loses charge. This can lead to a dead battery. However, when it’s left discharged for longer, the battery life will permanently reduce.
Headlights or electronics left on: Leaving headlights and electrical system accessories on when the engine is idling or off can cause deep discharging, which shortens battery lifespan. Malfunctioning electrical components or wiring issues may cause parasitic drain — drawing energy even when the vehicle is off.
Failed alternator: A malfunctioning alternator may not produce the correct voltage to charge your battery. This can lead to overcharging or a dead battery. Over time, this can reduce your battery’s lifespan.
Extreme temperatures: Extreme heat can evaporate battery water and cause corrosion. Whereas, extreme winters can slow down electron flow and freeze batteries. Both damage the battery and reduce its overall capacity.
Corrosion or loose battery terminals: This can affect electrical conductivity and increase resistance, which strains the battery and accelerates wear.

Dealing with a dead battery can be tough.
Read on to explore what you can do.

What to Do if Your Battery Is Dead?

As we’ve covered above, many factors can cause your car battery to die or lose charge.
You can always jump-start your vehicle if your car battery is dead, though it’s best to have a professional inspect it to rule out other potential issues.

Here’s how to jump-start your vehicle using another vehicle:

Park the two cars close together (at least 18 inches apart) so the jumper cables can reach both batteries. Switch off the engine.

Open both car hoods and grab your jumper cables.

Attach one red clamp on the jumper cables to the positive terminal of the dead battery. Then, attach the other red clamp to the positive terminal of the functioning battery.

Attach one black clamp to the functioning battery’s negative terminal. Connect the remaining free black clamp to an unpainted metal part of the car with the dead battery. A nut on the engine block is ideal.

Start the engine on the vehicle with the functioning battery. Wait for a few minutes before starting the car with the dead battery. Leave both cars running for a couple of minutes.

Disconnect the jumper cables in the reverse order you attached them.

Drive your car for around 15 minutes to recharge the battery fully.

Note: Don’t try to jump-start a conventional battery if the top is wet or the battery looks swollen. Get a professional to look at it.

What if a new battery doesn’t solve the problem?
Let’s explore other reasons a car won’t start.

Are You Sure It’s The Battery?

Here are some other common issues besides a dead battery that may cause starting issues:

Worn starter motor: If you hear a continuous or single clicking noise when starting your vehicle, you might have a faulty starter motor. That said, starter motors may also die a silent death, rendering you unable to start your car.

Empty fuel tank: If you can’t remember the last time you filled up, your car may be out of gas.

Faulty ignition switch: If it isn’t your car battery, the ignition switch could be to blame. If so, your headlights will turn on and illuminate normally, but the car won’t start.

Faulty fuel pump: When you start your car, you should hear a faint ‘buzzing’ sound after turning your key. If there’s no buzz, you likely have a fuel pump issue.

Blocked fuel filter: A blocked fuel filter prevents gas from reaching the engine. To prevent this, you should replace it every 60,000 miles.

Faulty charging system: When the charging system fails, the battery keeps losing voltage without recharging. As a result, your lights may vary in brightness as you accelerate and brake.

Resolve Car Battery Troubles with AutoNation Mobile Service

Watching out for a weak battery can help ensure you aren’t stranded in the middle of nowhere. That’s why we’ve covered those signs and everything you need to know about car batteries above.

Still, it’s best to get professional help to resolve battery issues before they can cause further damage.

Why not call AutoNation Mobile Service?
We’re a mobile auto repair and maintenance company that offers upfront pricing and a 12-month, 12,000-mile repair warranty.

Contact us, and we’ll resolve auto issues right from your driveway, whether you need an automotive battery or tire service.