A battery charger for your vehicle can recharge a dead or dying car battery so your vehicle can start and get you on the road to where you need to go. This device is a great addition to your vehicle’s emergency kit, alongside a tire inflator, flashlight, and first aid kit.
The best battery charger for your motorcycle, car, or truck depends on how you want to use it, how often you use it, and how quickly you want your battery to charge. Take a look at the top products below to find out what some of the best battery chargers have to offer.
- BEST OVERALL: NOCO GENIUS10, 10-Amp Fully-Automatic Smart Charger
- BEST BANG FOR THE BUCK: AmazonBasics Battery Charger 12 Volt 2A
- BEST PORTABLE: DBPOWER 800A Portable Car Jump Starter
- BEST SOLAR: SUNER POWER 12V Solar Car Battery Charger
- BEST FOR DEAD BATTERIES: Clore Automotive JNC660 1700 Amp 12V Jump Starter
- BEST FOR FAST CHARGING: Schumacher SC1280 Automatic Smart Battery Charger
- BEST TRICKLE CHARGER: Foval Automatic Trickle Battery Charger 12V
Types of Car Battery Chargers
Car battery chargers are categorized into three main types based on their intended purpose. These types are a charger, maintainer, and restorer. Each type has a specific purpose, so knowing the differences can help you select the best battery charger for your needs.
It’s also important to keep in mind that a battery charger is a short-term solution. These are helpful, but they won’t heal all problems. If you find yourself continuously relying on a battery charger, you may need to consider replacing the battery or having your alternator checked.
Along with other simple vehicle maintenance, charging your car’s battery should not be difficult. With a straightforward battery charger, you won’t have to worry about complicated procedures. It is the most common, affordable, and basic form of a car battery charger, typically featuring a low-amp trickle charge that can take up to 24 hours to fully charge your battery. The rate of charge depends on the size of your battery and output of the charger.
These chargers don’t monitor the charge of your battery, so you need to check on the progress every few hours to ensure that you do not overcharge the battery. Leaving a regular battery charger to charge your vehicle can lead to a serious maintenance mistake if the battery becomes fully charged and continues to overcharge. An overcharged battery can melt, swell, or simply die. However, these basic chargers can typically be used with almost any vehicle battery, making them ideal for emergencies.
A maintainer battery charger will monitor the battery’s power level and stop charging when it is full. However, the main purpose of a maintainer is to provide ongoing power to a battery without overcharging or allowing the battery to run out of power. This is usually attained with a lower amp setting that consistently powers the battery while you use it.
Solar-powered maintainers are often used for camping. You can enjoy the music from your car stereo without wasting fuel or battery power, as the solar energy is collected and used to maintain the charge on your car battery.
When a car battery runs low on power or drops completely below the required threshold to start your vehicle, the battery begins to crystallize and forms a buildup of lead sulfate crystals. While this buildup prevents the battery from ever returning to a full charge, a battery restorer can detect battery sulfation and begin to clear the buildup using a desulfator.
The result is that your battery regains some of its former life. The results vary greatly from battery to battery based on several factors, but the biggest factor is how long the battery had been sitting with a very low charge. Most restorers also are designed to charge and potentially maintain your batteries, though these additional features come with a higher price.
What to Consider When Choosing the Best Battery Charger
Before choosing a battery charger for your car, check out some of the most important shopping considerations to keep in mind so that you don’t unintentionally make any mistakes with your car.
Automatic vs. Manual
Car battery chargers either have an automatic or manual function. While the main difference is how much time you want to spend monitoring the charging process, there are other factors that differentiate the two types.
- Automatic car battery chargers have quickly replaced manual chargers as the most frequently used battery chargers, because automatic chargers remove the guesswork from charging your car battery. They monitor the battery, charging it to full, then automatically switch it to a maintenance mode or turn it off to prevent overcharging. This makes them a great option for overnight charging.
- Manual car battery chargers are typically less expensive because they require you to keep a watchful eye on your car battery to prevent it from overcharging. Due to this requirement, they are often turned off when the battery reaches a close-to-full charge to avoid the potential of accidentally overcharging. However, this results in a lower battery charge overall.
Electric vs. Solar
Battery chargers need to get their power from somewhere in order to transfer that accumulated power to your battery. This can typically be split into electric and solar power.
- Electric-powered battery chargers have either direct power from a power cable that connects to your power outlet, or they have stored power. Stored power also is gathered through a connection to the electrical outlet, but it can be disconnected and taken on the road as a portable charging option. These chargers dominate the market because it is much easier and more convenient to plug in a battery charger than waiting for the sun to come out.
- Solar-powered battery chargers offer the power of solar energy, which has the added bonus of being completely free. The portable design of these chargers makes them a great option for road trips and camping. However, the drawback to solar-powered chargers is that the sun is not always readily available, which greatly limits the reliability of this device.
Voltage and Amperage
Battery charger manufacturers will normally indicate the charger’s voltage and amperage, with the voltage measured in volts and amperage measured in amps (A). Voltage can be understood as a type of pressure or current that pushes charged electrons through a conducting loop.
With this in mind, the pressure or voltage being pushed must be able to be received, which is why a charger and battery must have compatible voltage ratings. The voltage of a battery charger indicates the type of batteries it can charge. For instance, a 6-volt charger shouldn’t be used to charge a 12-volt battery, though there are chargers that are capable of working with multiple voltages.
The amperage of a battery charger reflects the amount of energy it can dispense over an hour-long period, meaning that the amps of a charger is one of the best ways to determine how long it will take to charge your battery with that particular charging device. A car battery charger will normally have amperage ratings between 2 amps and 15 amps, though solar-powered chargers may be as low as 0.25 amp, depending on their capacity.
The time it takes to charge a battery is highly dependent on several factors, including the capacity of the battery, the source of power for the charger, the power output of the charger, and whether the battery is being used while charging. The total capacity of your battery can be determined by reading the details provided by the battery manufacturer or possibly noting the information on the side of the battery. A battery charger that is powered by an electrical outlet will provide ongoing power until the battery is charged, but a solar-powered or battery-powered charger may run out of available energy before the car battery can be fully charged.
Battery chargers have an energy output that is measured in amps. As long as the battery is not in use, you can use this number and the total capacity of your battery to roughly determine the amount of time it will take to charge. For instance, a 48-amp battery will take 24 hours to charge from a 2-amp battery charger, while it will take only five hours with a 10-amp charger. If the battery is in continuous use, then it will never be fully charged, but it can be maintained with a battery maintainer.
Battery chargers may be used in the shelter of your garage, but they also could be used on the side of the road in pouring rain or heavy snow. Because of their potential use in inclement weather, they need to be properly protected against the elements to ensure that you can charge your battery in an emergency. This protection also helps extend the life of the charger so that you don’t have to replace it after a little rain.
Look for water-resistant or waterproof battery chargers and consider both dust-resistant and impact-resistant products to make sure that your charger will continue working in undesirable conditions. For further weatherproofing, there are battery chargers that come with protective cases to ensure that your charger is kept safe when it is not in use.
While the main purpose of a car battery charger is to charge the battery of your car or other vehicles, manufacturers have started including convenient extras. Recognizing society’s need for multipurpose devices, some chargers include features like built-in radios, LCD screens, additional charging ports for small devices, and spark-proof exteriors.
- Built-in radios allow you to enjoy some music while the car battery charges, making it a pleasant addition to chargers that are maintaining the battery charge on a stored car in your garage.
- LCD screens give you a clear view of the charger and battery details, so you won’t have to try to decipher a series of small lights to figure out when you should stop charging.
- Additional charging ports for your devices, like your smartphone, are always a great option. Having a charged phone helps in any emergency.
- Spark-proof protective exteriors are a feature that you will hopefully never use, but in the case of a spark or flame coming into contact with the charger, this should come into play as a safeguard.
Given that battery chargers are frequently used in emergency situations, it’s helpful when a battery charger is easily portable. With battery chargers, this specifically refers to the size, weight, internal stored energy capacity, and whether there are features like a carrying handle that would make the charger easier to carry.
Many car battery chargers are now made small enough to fit in the glove compartment, but more powerful chargers will still need to ride in the trunk. These larger chargers will typically feature a carrying handle that makes them easier to manage. Also, keep in mind that no matter the size of the charger, it needs to be able to store electricity for it to be portable. Chargers that work only when they are plugged into a power outlet are not considered portable.
Our Top Picks
The top-rated products below were chosen based on category to help you find the best battery charger for your dead or dying car battery.
The NOCO GENIUS10 10-amp battery charger, maintainer, and restorer is a fully automatic device that produces a consistent 10-amp charging output, which is ideal for quickly charging a battery. You can use this charger with 6-volt or 12-volt batteries, and it has an ambient temperature sensor that will adjust the charge to help eliminate overcharging in hot temperatures and undercharging in cold temperatures.
The charger also can be used to maintain your battery, automatically switching to maintenance mode when it detects that your battery has a full charge. It can remain in this mode for 24 hours a day with no risk of overcharge, according to the manufacturer. You also can use this charger to restore lost battery capacity with the automatic battery sulfation and restoration feature.
If you store recreational vehicles, classic cars, motorcycles, or any other vehicles that have a 6-volt or 12-volt battery, then this car battery charger is a great option for ensuring that your vehicles remain charged while in storage. The charger plugs directly into a standard 120-volt outlet to provide a trickle charge output of 2 amps that will steadily charge your car battery until it has reached its stored energy capacity.
After the battery is full, the charger will automatically switch to a maintenance mode to ensure the battery remains full without overcharging. This battery charger comes with fused alligator clips to securely connect to your battery, and the case is made of durable, spark-proof plastic. You also get the ease of mind that comes with reverse polarity protection. If you connect the clips to the wrong battery terminals, the unit won’t provide power until the connection is corrected.
It is never a bad idea to have a fully charged portable car battery charger in your glove box in case your battery runs low, or if you need to provide a jump-start to a freezing engine. This compact battery charger is designed with a peak output of 800 amps, which is the ideal current for jump-starting vehicles that have up to a 7.2-liter gas engine or 5.5-liter diesel engine. It also has enough stored energy to jump-start your vehicle up to 20 times, so you won’t have to worry if the engine doesn’t turn over the first time.
You also can use this device as a simple charger with a high charging output of 18 amps. The charger comes with a set of heavy-duty clamps and cables as well as an LCD display screen and an USB port to charge your phone, tablet, or laptop. This helpful device has a built-in compass and a flashlight that is ideal for ensuring that you properly connect the charger to the battery.
Simple, effective, and free, solar energy is a great way to keep your 12-volt car, motorcycle, boat, or ATV battery fully charged using this solar-powered battery charger. The charger outputs 0.5 amps or 6 watts of electricity and features a built-in blocking diode that prevents the reverse discharge of your battery if it is connected incorrectly. You can connect the charger through the cigarette lighter socket on your vehicle or connect it directly to the battery with the included clamps.
An option for camping or boating, it will trickle-charge your batteries as long as there is sufficient sunlight available. The solar battery charger is simple to set up, only requiring you to position the charger with the crystalline solar panel in full view of the sun.
While other battery chargers are typically used to charge a low battery in your garage, this emergency jump-start battery charger allows you to jump-start a dead battery with an impressive peak output of 1,700 amps. The typical car requires approximately only 800 amps to start the car, so you can use this battery charger on larger vehicles, like a truck or an RV.
Once the vehicle is started, the charger can stay connected to rapidly charge your battery with a charging output of 22 amps. This allows you to charge a 40-amp battery in just two hours. The charger comes with a carrying handle, and it also has 46-inch-long cables that end in industrial-grade clamps that are able to penetrate layers of corrosion on your battery to ensure a good electrical connection.
When you need to charge your car battery in a hurry, you need a charger like this one. It has a 15-amp charging output that can fully charge a 45-amp battery in just three hours. The battery charger also features a fully automatic sensing and operating system to ensure that your battery receives the optimal amount of power. This includes the ability to detect whether the charger has been connected to a 6-volt or 12-volt battery and to determine if the charger has been connected to the battery properly. The charger will not supply power if the battery is not connected properly.
When the battery is full, the automatic charger and maintainer will switch to a 3-amp maintenance output to ensure that your battery doesn’t overcharge. This battery charger has a bright LED display, a simple carrying handle for better portability, and it is compatible with most 6-volt and 12-volt batteries.
If you prefer to slowly charge your battery to ensure that it doesn’t overcharge or lose any stored energy capacity due to rapid charging, then this automatic trickle battery charger with a low 1-amp output is a great option. It also protects against the potential of reverse polarity if you connect to the incorrect battery terminals. The battery has a long 8-foot output cord so that you won’t have to worry about maneuvering your vehicle to reach a short charger.
This trickle battery charger has four charging modes that it automatically switches between to provide the optimal amount of power for the battery. The charger also has a built-in fire and spark safety system that checks for a correct connection to the battery terminals before it will begin providing power. If you don’t have a car, you can use this charger with a variety of 12-volt batteries including motorcycles, ATVs, boats, or even some airplanes.
Tips for Using a Battery Charger
Car battery chargers are designed to work with car batteries, but this process can be very dangerous if you don’t know how to properly connect or use the charger. Always begin by shutting off the vehicle, removing the key from the ignition, and checking to make sure the lights, radio, and other electrical accessories also are turned off before touching the battery.
When you connecting the battery charger to the battery terminals, you can get interference from dirt, oil, and other debris that has built up on the battery. To resolve this issue, clean the battery terminals with a dry rag before connecting the charger. To be blunt, you should never wash the battery with water; and if you suspect that the battery or the battery terminals are wet, you shouldn’t connect the battery charger, as this can cause it to spark or ignite.
- Before using a battery charger, shut off the vehicle and remove the key from the ignition, ensuring that all electrical devices, like interior cabin lights, also are turned off.
- Make sure that you clean the battery terminals before attaching the clamps to prevent interference.
- Never use a battery charger if you see or suspect that the battery terminals are wet, as this can cause the battery to spark or even ignite.
FAQs About Battery Chargers
If you still have questions about battery chargers for the car, these frequently asked questions and their answers below may help.
Q. How many amps should a car battery charger have?
There is no set number of amps that a car battery charger should have. Some people prefer a smaller 2-amp charger that will take about 24 hours to charge a 48-amp-hour battery, and others choose a 10-amp charger that can rapidly recharge the same battery in just five hours.
While having a faster charger may seem like the best option, smaller chargers have been shown to be more beneficial for extending the life of your battery. However, if you don’t have a day to wait for your battery to charge, then a larger charger is a better option.
Q. How long do car chargers take to charge batteries?
It usually takes about four to 11 hours to charge batteries, depending on the type of battery, type of charger, and the power specifications of each.
Q. Can you leave your car battery charging overnight?
Yes, you can leave your car battery charging overnight, but you should not leave the battery charging for longer than 24 hours to prevent overheating.
Q. How often should you charge your car battery?
If your car battery is still working correctly and the alternator in your vehicle is providing power to the battery during use, then you shouldn’t need to recharge your battery for about five years. If you need to recharge it more often, then you should consider replacing the battery.
Q. How do I know when my car battery is fully charged?
Most battery chargers will provide you with an accurate measurement of the power remaining in the battery so that you know when it is fully charged, or they will automatically stop charging the battery once it reaches capacity.
Alternatively, you can use a voltmeter to measure the power across the positive and negative terminals on the battery. Any reading less than 12.6 volts on a 12-volt battery indicates that the battery does not have a full charge.