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What is the best car battery charger, and how long does it take to charge?
Car batteries don't last forever.
You may accidentally leave the lights on in your car and drain them. Plus, the elements play a role -- freezing weather can drain up to 60% of the power from your vehicle's battery.
Whichever situation you and your car battery happen to be in, the best car battery chargers can get you back on the road in time. We researched the five best car battery chargers of 2023 to save you time and money.
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- Alternator check
- LCD screen
- USB port and 120V outlet
- No internal battery
- 6-foot power cable might be too short for some workshops
Tech Specs: Running: 30A | Engine start: 80A | Maintain: 2A
This is an easy-to-use battery charger and jump starter that's perfect to keep in your garage for regular maintenance or emergency use. It features simple push-button controls for jump starting, charging, and checking your alternator. It even has a 120V outlet and USB port for charging mobile devices or powering small appliances.
You can easily read your battery's voltage and charging status with the LCD screen -- no more squinting at confusing meters. The 80A engine start mode can get you going in about 60 seconds, and there's a quick charge function for when you need to top up in a hurry.
- Voltage switch
- Two connection types
- Compact design
- No engine start
- Might take over 40 hours to fully charge a dead car battery
Tech Specs: Running: 1.5A | Engine start: N/A | Maintain: 0.5A
Keeping up with regular battery maintenance doesn't mean you have to spend a fortune on fancy tools. This trickle charger from Black+Decker costs about $30, and it's perfect for both 6V and 12V batteries like those you'd find in lawn mowers, motorcycles, and most cars and trucks.
You can connect it to the battery via clamps or rings for safe and secure charging, and a switch lets you quickly and easily select the battery type you want to charge. It also has LED indicator lights to warn you against reversed connections, which can be dangerous, and to let you know when the battery is finished charging.
- Engine start mode
- Quick charge mode
- Alternator check
- Short clamp cords
- Small power cord
Tech Specs: Running: 15A | Engine start: 50A | Maintain: 3A
I actually own this model of charger/maintainer, and I can say with confidence that it's a great choice for all skill levels. The backlit LCD screen makes it easy to see charging status, reversed connection warnings, and charging mode selections.
The push-button controls make it quick and easy to check battery voltage, test the alternator, jump start your car, or charge the battery. With the 15A quick charge mode, it took just over three hours to bring my old Chevy Cobalt's battery back to full after being drained by an interior light.
Also: The 5 best portable jump starters
The unit also automatically switches from quick to trickle charging when the battery reaches full capacity to avoid overcharging that can cause damage.
- 17-foot power cable
- Flash reprogramming
- Memory saver mode
- Not ideal for smaller garages
Tech Specs: Running: 60A | Engine start: 275A | Maintain: 4A
The ProSeries from Schumacher Electric is a battery charger meant for anyone who has heavy duty vehicles, like semi-trucks or diesel engine vehicles, or anyone who runs an automotive shop. It has a 15A fast-charge mode, 275A engine start, and 4A trickle charge feature.
It's also capable of flash reprogramming vehicle computers to fix minor software problems that may affect things like gas mileage and engine performance. It even has a memory saver mode to quickly reload computer settings after a battery is charged from zero or replaced.
The unit has a 17-foot power cable as well as wheels and a retractable handle to make it easy to maneuver around the shop and reach just about any vehicle bay.
- Includes an air compressor
- Built-in handle
- Power inverter
- Short clamp cables
- No trickle charge mode
Tech Specs: Running: N/A | Engine start: 1200A | Maintain: N/A
This is another battery charger that I personally own, and I keep it in my car for roadside emergencies. Not only can it jumpstart your car and charge the battery, it also has a 500W power inverter for charging mobile devices and a 120 psi air compressor if you get a flat while you're out and about.
The built-in handle makes it easy to transport, and it's compact enough to keep in the trunk of my Trailblazer. It has a 120V outlet, 3 USB ports, push-button controls, and an easy-read LCD screen. The battery clamp cords are a bit on the short side, but since you don't need to keep the unit plugged into a wall to use, it's not much of an issue.
What is the best car battery charger?
The DeWalt 30A charger is the best car battery charger based on price, running amperage, engine start amperage, power cord length, usability, inclusion of USB ports and power outlets, and more. This table illustrates key factors from each of the car battery chargers making our list:
Best car battery chargers | Price | Running | Engine start |
DeWalt 30A charger | $119 | 30A | 80A |
Black+Decker 6/12V charger | $29 | 1.5A | N/A |
Everstart Maxx 15 amp charger | $64 | 15A | 50A |
Schumacher Electric DSR122 ProSeries 275 amp charger | $508 | 60A | 275A |
Everstart Maxx 120 amp portable charger/air compressor | $98 | N/A | 1200A |
Which is the right car battery charger for me?
If you want something to maintain your car or truck battery, choose a charger that is best suited for 12V batteries and is capable of at least 15 running amps. This way, you don't damage anything, and it won't take three days to charge your battery.
For larger vehicles, you want something with a higher running and engine start amperage, while smaller batteries like those found in lawn mowers and motorcycles require a charger that is suited for 6V units.
This buying tree can help you decide which car battery charger is right for you:
Choose this car battery charger… | If you want or are… |
DeWalt 30A charger | Best car battery charger |
Black+Decker 6/12V charger | Best budget charger |
Everstart Maxx 15 amp charger | Best for quick battery charging |
Schumacher Electric DSR122 ProSeries 275 amp charger | Best for larger vehicles like trucks |
Everstart Maxx 120 amp portable charger/air compressor | Best for multi-use: air compressor and charger |
How did we choose these car battery chargers?
I looked at a variety of retail prices to put together a list of car battery chargers to fit almost any budget and toolbox. I considered readers who may only want a car battery charger on-hand for emergency charging, as well as people who are serious about at-home car maintenance.
How long does it take to charge a car battery with a charger?
It all depends on the running amperage of your charger and the amp hours rating of your car battery. The average car battery has a rating of 70 amp hours, so if you have a charger capable of 10 running amps, it'll take about 7 hours to bring a battery back to full if it was run down completely.
The best way to figure out charging time is to divide your battery's amp hour rating by the running amp rating of your charger (70ah/10amp = 7 hours).
How long can a car battery sit before it loses charge?
It takes about a week of sitting idle for a car battery to drain down to the point where it won't start the engine. If you work from home, or just generally don't drive that much, you should start your car once a week and let it run for 5-10 minutes to maintain the battery as well as circulate engine oil to prevent clogging.
Extreme temperatures can also drain your battery, including high heat in the summer and frigid nights in the winter. You'll want to connect a trickle charger during temperature warnings to maintain your battery or drive more often.
Is it bad for a car battery to drain completely?
If it happens once, it's not going to affect much. But if it happens fairly often, that's an indicator of damaged posts in lead-acid batteries or other issues. Constantly draining and charging a battery can cause it to "bloat," which could lead to dangerous cracking and leaking (battery acid is extremely caustic and toxic), or even explosions and fires.
Moreover, corroded posts are an indicator of damage, so be on the look out for white or greenish flaky buildup where the wires connect to the battery. If it's very light buildup, you can disconnect the battery from your car and clean the posts and connections with a wire brush. But if the build-up is excessive, it's time to change out the battery. Thankfully, many automotive retailers give you discounts on new batteries if you bring the old one in to be recycled.
Can you overcharge a vehicle battery with a trickle charger?
Yes, you can. You want to pay close attention to the manufacturer's instructions when it comes to operating the charger. In some cases, you'll want to leave it connected for up to 48 hours, depending on the charger's power capacity.
If you leave it connected too long, it can cause permanent damage to the battery by overheating it.
Are there alternative car battery chargers worth considering?
We offered a range of chargers based on vehicle type, pricing, and multi-purpose. If you want more choices, here are some great ones to consider: