The 7 Best Car Battery Chargers for Roadside Emergencies

Thomas HenggeProsReady for anythingWide range of capabilitiesConsOccupies a bit more space than the competitionNoco’s Genius 10, the brand’s flagship single-vehicle charger, offers many cool features, including the ability to “force charge” a battery so dead it won't generate any voltage when you hook it up. (Most modern chargers won’t do this.) Maintenance and “desulfation” modes extend your battery's useful life while keeping it ready to go.Unlike smaller, less ambitious chargers, the Genius 10 charges a vehicle battery to full power in the shortest safe time. It can even charge the new generation of lithium-ion car batteries, like the complex, expensive units fitted to many newer BMWs.Key SpecsPower10-amp chargerModesQuick charge, maintenance, desulfation modes with auto-detectDimensions 7.1 x 3.6 x 2.3 in.ProsHigher power than the competitionSimple useAll the basic features are here at a very low price, including protection from reverse clamping and a “float mode” for fully charged batteries.The included set of bolt-on leads lets you quickly connect and disconnect the charger. Operation couldn’t be simpler: a green light shows the Motopower is on, and a red light indicates charging status. With 1.5 amps of power, it charges slightly faster than most competitors in the low-price bracket.Key SpecsPower1.5-amp chargerModesMaintenance and quick charge modesDimensions 5.12 x 2.56 x 1.57 in. Advertisement - Continue Reading BelowProsSimplePowerfulNo quick-connects to wear outConsHeavyDoesn’t offer a force charge or diagnostic informationThink of this 15-amp charger as a miniature version of the shop-grade Schumacher. It’s also the form and function that will be most familiar to older or experienced users. The included clamps are high-quality and should fit most cars. Just clamp on, plug in, and select one of three modes.The 15-amp rapid charge is slightly more than the competition can manage, and a carrying handle makes it easy to place where you want it.Key SpecsPower15-amp chargerModesThree maintenance/charge modes for slow or fast charge-upDimensions 10 x 5.25 x 7.5 in.ProsSmall and lightweightLifetime customer serviceConsMaintenance mode onlyThis charger is compact, light, easy to operate, and almost bombproof. It delivers a 3-amp charge, then automatically switches to float mode to maintain proper voltage and prevent overcharging.A two-color LED indicates charging status, and if the battery voltage drops below a certain level, it resumes full charging output in adaptive mode. It’s compatible with most automotive batteries and can switch between 6- and 12-volt batteries with the push of a button. Its battery clamps are spark-proof, and the Battery Tender 3-Amp will automatically detect reverse polarity. It comes with a 5-year warranty and lifetime customer service.Key SpecsPower3-amp chargerModesMaintenanceDimensions3.4 x 11.1 x 9.4 in.Advertisement - Continue Reading BelowProsCharges four vehicles at onceAble to float and reconditionDealerships and race shops that used to scatter CTEK individual chargers throughout the building are now switching to the multi-vehicle Noco 2x4 model. It weighs just under 8 pounds, mounts to a wall, and can handle four vehicles at the same time, each in a different mode.Want to float charge one car, recondition another, and bring two other dead batteries back to life in force-charge mode? Not a problem.Key SpecsPower8-amp total charger (across 4 vehicles)ModesQuick charge, maintenance, and desulfation modesDimensions 9.88 x 5.71 x 10.79 in.ProsAutomatically adjusted charge rateFloat mode Reverse hook-up protectionConsLow charge rateMaintenance-only modeIf you own a vehicle you only drive occasionally, an under-the-hood charger saves the hassle of disconnecting it from the battery and storing it each time you want to go for a cruise.The compact Schumacher SC1300 mounts under the hood to supply up to 1.5 amps, while a built-in microprocessor automatically adjusts the charging rate to maintain an ideal charge state. Float mode delivers a small current when needed.Reverse hook-up protection prevents the charger from working if the battery clamps are installed in reverse polarity, and the Schumacher automatically detects 6-volt or 12-volt batteries.Key SpecsPower1.5-amp chargerModesMaintenanceDimensions9 x 2 x 5.9 in.Advertisement - Continue Reading BelowProsSolar powered; no electrical outlet neededCharge controller prevents overchargingConsSlow 1.38-amp chargingIf an electrical outlet isn’t available or if you just want to use the sun to keep your battery topped off, the Sun Energize solar-powered charger is a reliable option. It trickle-charges a variety of automotive batteries, as well as some lithium batteries.A built-in charge controller prevents overcharging; charging stops when a battery is topped off and automatically resumes when it drains.An LED indicator shows charge and battery conditions. The 20.1 x 13.8 x 0.7-inch solar panel is larger than the other chargers here, but it’s built to handle high winds and heavy loads and is IP65 waterproof.Key SpecsPower1.38-amp chargerModesMaintenanceDimensions20.1 x 13.8 x 0.7 in.Doug Newcomb splits his time between Hood River, Ore., and Todos Santos, Mexico. He's been writing about technology and cars for more than 30 years for Wired, Rolling Stone, Road & Track, Automobile, PCMag.com, Playboy and numerous other publications. He cofounded the C3 Group in 2013 to produce automotive industry events in New York, San Francisco, Washington, D.C. and at SXSW in Austin. C3 Group was acquired by Informa in 2018. When he's not writing, he's riding a surfboard Jack Baruth is a writer and competitor who has earned podiums in more than fifteen different classes and sanctions of automotive and cycling competition, in both amateur and professional capacities, as well as an enthusiastic hobbyist musician and audiophile who owns hundreds of musical instruments and audio systems. His work has appeared in Bicycling, Cycle World, Road & Track, WIRED, Wheels Weekly, EVO Malaysia, Esquire, and many other publications. His original design for a guitar, the Melody Burner, has been played by Billy Gibbons, Sheryl Crow, and others.Matt Crisara is a native Austinite who has an unbridled passion for cars and motorsports, both foreign and domestic. He was previously a contributing writer for Motor1 following internships at Circuit Of The Americas F1 Track and Speed City, an Austin radio broadcaster focused on the world of motor racing. He earned a bachelor’s degree from the University of Arizona School of Journalism, where he raced mountain bikes with the University Club Team. When he isn’t working, he enjoys sim-racing, FPV drones, and the great outdoors.