What a DuraStar Charger Does
A DuraStar charger is a battery charging device sold by AutoZone, designed to recharge 12-volt car batteries and maintain their charge over time. It plugs into a standard household outlet and connects to your vehicle's battery with clamps. DuraStar chargers come in different models — some are basic trickle chargers for slow overnight charging, while others are faster chargers that can restore a dead battery in a few hours.
The charger works by converting AC power from your wall outlet into DC power that your battery can accept. Most DuraStar models include safety features like reverse-polarity protection, which stops the charger if you connect the clamps backward, and automatic shutoff when the battery reaches full charge.
You buy DuraStar chargers at AutoZone stores or through their website. Prices vary by model and charging speed, typically ranging from around $30 for a basic trickle charger to $150 or more for faster, multi-stage chargers. AutoZone also rents some charger models by the day if you want to test one before buying.
Key Takeaways
- DuraStar chargers plug into a household outlet and connect to your car battery with clamps to recharge 12-volt batteries.
- Different models charge at different speeds — trickle chargers take 12 to 24 hours, while faster models can charge a dead battery in 2 to 8 hours depending on the model.
- Most DuraStar chargers include automatic shutoff and reverse-polarity protection to prevent damage to your battery or charger.
- You can purchase DuraStar chargers at AutoZone locations or online, or rent certain models by the day to see if the charger meets your needs.
Types of DuraStar Chargers and Their Charging Speed
DuraStar makes several charger models, each designed for different situations. A trickle charger delivers a small, steady amount of power — usually 2 amps or less — and takes 12 to 24 hours to fully charge a dead battery. These work well if you have time and want to avoid stressing an old battery. A standard charger typically delivers 10 to 20 amps and can charge a dead battery in 4 to 8 hours. A fast charger delivers 40 amps or more and can charge a battery in 1 to 3 hours, though this puts more stress on the battery and is best for newer batteries in good condition.
Some DuraStar models are multi-stage chargers, meaning they automatically adjust their charging speed as the battery fills. They start fast when the battery is nearly empty, then slow down as it approaches full charge. This protects the battery from overcharging and heat damage. Check the product label or AutoZone's website to see which model you are looking at, because the name alone does not always tell you the charging speed.
How to Connect and Use a DuraStar Charger
Before you start, make sure the charger is unplugged from the wall outlet. Open your vehicle's hood and locate the battery — it is a rectangular box with two thick cables attached, one red and one black. The red cable connects to the positive terminal (marked with a + sign), and the black cable connects to the negative terminal (marked with a − sign).
Attach the red clamp from the charger to the positive terminal first, then attach the black clamp to the negative terminal. Do not reverse this order — connecting black first and red second is the correct sequence for safety. Once both clamps are find, plug the charger into a household outlet. Most DuraStar chargers have an indicator light that shows whether the battery is charging. When the light changes color or turns off, the battery is fully charged. Unplug the charger from the wall, then remove the black clamp first, followed by the red clamp.
Never leave a charger connected to a battery unattended for more than a few hours after it reaches full charge, even if the charger has automatic shutoff. If you are charging overnight, use a trickle charger or a multi-stage charger, which are designed for extended connection time.
When to Use a DuraStar Charger Versus Other Options
A DuraStar charger makes sense if your battery is dead but the vehicle itself is in good working order. If your car will not start and you have a charger at home, charging overnight or over a few hours is often cheaper than calling a tow truck or paying for roadside service. A charger is also useful if you own an older vehicle you do not drive often, because you can use a trickle charger to keep the battery topped up between uses.
However, a charger is not the right tool if your battery is damaged, leaking, or more than 5 to 7 years old and will not hold a charge even after a full recharge. In those cases, the battery itself needs to be replaced, not recharged. If you are stranded on the road with a dead battery and no access to an outlet, a portable jump starter (a battery-powered device you keep in your car) works faster than a charger. If your car has a chronic starting problem even with a fully charged battery, the issue is likely your alternator or starter, not the battery, and a charger will not fix it.
Safety Considerations When Charging a Battery
Car batteries contain sulfuric acid and can produce hydrogen gas while charging, so ventilation matters. Always charge in a garage with the door open, a driveway, or another outdoor space — never in a closed room or basement. Keep the charger away from water and do not use it in rain or wet conditions. If battery acid has leaked onto the charger clamps or your hands, wash with water when ready and do not touch your face.
Wear safety glasses if you have them, especially if the battery is old or visibly damaged. Do not smoke or create sparks near a charging battery. If the battery is cracked, leaking, or swollen, do not attempt to charge it — take it to AutoZone or a repair shop for safe disposal and replacement. If the charger itself is damaged, cracked, or the cord is frayed, do not use it.
Maintenance and Storage of Your DuraStar Charger
Store your charger in a dry place, such as a garage shelf or storage closet, away from extreme heat or cold. Coil the power cord loosely so it does not kink or fray. Before each use, inspect the clamps and cord for damage. If the clamps are corroded or the cord is cracked, the charger should be replaced.
If you use your charger regularly, check the clamp connections every few months to make sure they are tight and free of corrosion. If corrosion builds up on the clamps (a white, blue, or green crusty coating), clean it with a wire brush or a cloth dampened with vinegar. Do not submerge the charger in water or attempt to repair internal components yourself. If the charger stops working or will not hold a charge, AutoZone can test it for you or recommend a replacement.
Frequently Asked Questions
Can I use a DuraStar charger on a battery that is completely dead?
Yes. A completely dead battery can still be charged, though it may take longer than a battery that still has some charge. Start with a lower amp setting if your charger has one, and check the battery after a few hours. If the charger shows no activity after 30 minutes, the battery may be damaged and unable to hold a charge.
How long does it take to charge a car battery with a DuraStar charger?
Charging time depends on the model and the battery's condition. A trickle charger takes 12 to 24 hours, a standard charger takes 4 to 8 hours, and a fast charger takes 1 to 3 hours. Multi-stage chargers adjust their speed automatically, so the total time falls somewhere in the middle range.
What does it mean if the charger light is red instead of green?
A red light usually means the battery is still charging. A green light or no light typically means the battery is fully charged. Check your charger's instruction manual, because different models use different light signals. If the light does not change after several hours, the battery may not be accepting a charge.
Can I leave a DuraStar charger connected overnight?
Yes, but only if you are using a trickle charger or a multi-stage charger with automatic shutoff. Fast chargers should not be left unattended for more than a few hours. Even with automatic shutoff, unplug the charger once the battery is fully charged to avoid overcharging.
What should I do if the charger sparks or smells like burning plastic?
Stop using the charger when ready and unplug it from the wall outlet. Do not attempt to charge the battery again with that charger. The charger may be damaged internally and could pose a fire risk. Take it back to AutoZone for testing or replacement.