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Which car battery charger is best?
Those who have faced a dead battery know the sinking feeling and ensuing frustration. Now you have to wait for a tow or shell out for a new battery. But common draining events don’t have to ruin your day.
Whether you’re storing your battery long term or need a jump on the side of the road, the right car battery charger gives you just enough juice to get your vehicle rolling. For most at-home and on-the-road applications, the best car battery charger is the TowerTop 2/10/25A 12V Smart Battery Charger.
What to know before you buy a car battery charger
What is a car battery charger
Much like a charger for your phone or computer, a car battery charger is a portable device that can restore power to a depleted car battery. There are numerous kinds of car battery chargers out there, from trickle chargers to jump-starters. Which you choose will depend on your needs, and what type of battery you have in your vehicle.
How car battery chargers work
Car battery chargers are either powered by their own lithium-cell battery, or by AC power through your wall socket. They’re most commonly used on lead-acid batteries but are often also compatible with AGM and GEL batteries.
With a slew of settings to optimize your battery’s longevity and recharge rate, the charger box is your central point of command. From there, a negative and a positive cable with alligator clips extend out, which attach to their respective terminals on your vehicle’s battery to deliver the charge.
Car battery charger vs. trickle charger vs. jump starter
Car battery chargers can seem a little complicated at the start as every different model is technically a charger. Today, most chargers have cross-functionality, further blurring the line between each kind. There are a few important differences, however, that will determine which charger best suits your needs.
- Car battery charger: As the standard charger, these are designed to deliver a moderate amperage to your battery. Depending on your battery’s depletion level, these can be used to recharge your battery in a couple of hours so you can start your car again, or for more long-term maintenance applications
- Trickle charger: Unlike a regular car battery charger, these are made to deliver a low and steady current for long periods of time. Trickle chargers are best used for any vehicle battery you plan on storing for a period greater than two weeks and are most typically used as maintenance chargers over the winter.
- Jump starters: Like jumper cables, jump-start chargers deliver a large blast of juice to your car’s battery so that it can start again in an instant. These are excellent tools to have on hand in your trunk so you never have to wait for a tow or a kind stranger again.
How to use a car battery charger
Before you begin, make sure your car (if you haven’t removed the battery) and your battery charger are switched off. If you’re charging inside your car, start by connecting your positive alligator clip to the positive terminal of your battery. Leave your battery connected. Then, you’ll need to attach the negative clip to sufficient ground. This can be a bare metal part of your car’s chassis or a bolt on the engine block. If you’ve removed your battery, connect each clip to its respective terminal.
Once you’re all hooked up, go ahead and plug in your charger, turn it on, and select the proper settings to begin charging.
What to look for in a quality car battery charger
Amps
Car battery chargers typically have a moderate amperage rating compared to trickle chargers and jump-starters. This is usually in the 10-40 amp range. The higher the amperage, the faster your vehicle’s battery will recharge. If you’re looking to maintain your batteries, opt for a lower amp rating. If you want a charger that can restore batteries quickly or get you off the side of the road, you’ll need 25-40 amps (about two to four hours of charge time for a half-dead battery).
Volts
Voltage describes your vehicle’s battery capacity. You need to make sure that the charger you get has the matching volt rating to your battery. Most cars are six or 12 volts. Trucks and RVs are 12 or 24 volts. If you charge your battery with a higher-rated charger, you’ll risk overcharging and frying the battery. Go lower and you transform your charger into an energy sink that will further deplete the battery.
Functionality
Today, many chargers have multiple functions, allowing you to alternate charging modes depending on your needs. These modes modulate the amp current and monitor your battery’s charge so as to protect its longevity.
For users who need a good maintenance charger, features such as float mode and ambient temperature sensors are crucial for real-time monitoring so as to prevent overcharging. And if you’re working with old batteries, you’ll want a desulfator that can help restore some of your battery’s performance.
How much you can expect to spend on a car battery charger
Depending on the number of features it has, a car battery charger will cost between $30-$120.
Car battery charger FAQ
Do car battery chargers only work on cars?
A. Car battery chargers commonly work on lead-acid, AGM, STD and GEL batteries. This means you can use it for many vehicles on both land and sea, including boats, water scooters, RVs and motorcycles. They also work on machines such as electric-powered lawn mowers.
What causes a car battery to drain?
A. Batteries have a natural discharge rate, usually in the decimals, that causes them to lose voltage over time. When left in your car or vehicle, they are prone to what is called parasitic decay, which is caused by your car’s electrical devices that require about an amp a day to maintain. Lastly, common events such as leaving your lights on overnight, or running your electronics without the engine on for a long period of time can sap a battery of its power.
What are the best car battery chargers to buy?
Top car battery charger
TowerTop 2/10/25A 12V Smart Battery Charger
What you need to know: With three different amp currents, the TowerTop is a solid all-around charger for most vehicles.
What you’ll love: Not only can the TowerTop maintain or quickly charge your battery between its two-, 10- and 25-amp capacity, but its engine start aid feature delivers enough power to jump your car in under 120 seconds. At 12 volts, it’s compatible with most vehicles that have a lead-acid, GEL, AGM or STD battery. Its automatic charging system detects temperature and voltage changes so you never overcharge your battery in float mode.
What you should consider: This battery is not available for six- or 12-volt vehicles.
Where to buy: Sold by Amazon
Top car battery charger for the money
What you need to know: With two different volt and amperage ratings, this feature-packed budget charger is a great maintenance tool for any fleet of vehicles or arsenal of home appliances.
What you’ll love: This automated charger is designed to maintain or quickly recharge batteries using a 10-amp stream at 12 volts, or a five-amp stream at 24 volts. Its built-in fan and winter and summer modes adjust for ambient temperature to protect your battery. And the pulse repair function can be used to desulfate your battery.
What you should consider: You can’t use this battery to jump-start your engine or bring back a totally dead battery.
Where to buy: Sold by Amazon
Worth checking out
Schumacher SC1281 100-amp 30-amp 6-volt/12-volt Fully Automatic Smart Battery Charger
What you need to know: With its rugged design and convenient handle, this charger is perfect for outdoor applications, especially marine batteries.
What you’ll love: Offering both six- and 12-volt compatibility, this fully automatic charger works on common lead-acid batteries and deep-cycle marine batteries. The 100-amp jump-start feature can be used to get your car or SUV running in a pinch. The 30-amp stream makes this an excellent charger for anyone who needs a quick turnaround and isn’t interested in trickle chargers. The alternator tester is an added bonus to help you troubleshoot a car that won’t start.
What you should consider: Some users report overcharging their batteries when using this charger. Be sure to read the manual as there are important precautions and procedures to follow to ensure this doesn’t happen to you.
Where to buy: Sold by Amazon
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Karl Daum writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
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