Photo credit: / oatpenz studio

Keeping your car’s battery in good health is extremely important. Not only does it save you money in the long run from not having to prematurely replace your battery, you won’t have to deal with the inconvenience of your battery unexpectedly dying. At first glance, battery maintainers may appear to be the same thing as a battery charger, but they serve a different purpose.

Also known as float chargers, the job of a battery maintainer is to keep your car’s battery in good health if it isn’t being used for a long period of time. So if you plan on having your car sit in the garage for months, you’ll want to invest into a good quality battery maintainer.

We’ll jump straight into our list of the top 10 best battery maintainers, but if you want more information on battery maintainers and why they’re different than battery/trickle chargers, refer to our table of contents.

Updated 04/06/2020: You can currently save 11% off the MOTOPOWER Battery Charger/Maintainer, while the Schumacher 3A/12V maintainer is 17% off. DieHard also has its 2A charger/maintainer available with a 13% discount.

1. Editor's Pick: BATTERY TENDER® Plus

battery tender plus

BATTERY TENDER® has a wide range of offerings, but the BATTERY TENDER® Plus is our best overall pick. This is a 1.25A battery charger that is designed to fully charge a battery and maintain it at proper storage voltage without the damaging effects often found with trickle chargers.

Included with the BATTERY TENDER® Plus is a quick connect harness, along with ring terminals and alligator clips. The power cord length measures 6 feet (18AWG), while the DC output cord is 4.5-feet long (18AWG). Safety features include reverse polarity protection.

What makes this product the ideal battery maintainer is that it automatically switches from full charge to float charging mode to maintain your battery. The company also includes an impressive 10-year warranty.

Product features:

  • 1.25A battery charger
  • Includes quick connect harness, ring terminals, and alligator clips
  • Automatically switches from full charge to float charging mode
  • Spark proof, reverse polarity protected
  • Impressive 10-year warranty
Read More Best Jumper Cables


black+decker bm3b

BLACK+DECKER is likely a brand you are familiar with, and the company offers a fully automatic battery charger/maintainer that can charge 6- and 12-volt AGM, GEL, and WET batteries. It’s a fairly basic battery maintainer that is affordable and easy to use, simply connecting to your battery with battery clips or O-ring terminals. As a maintainer, it’ll automatically stop charging once the battery is fully charged or topped off, switching to float mode monitoring to maintain the battery.

Built-in circuit protection prevents overcharging, reverse polarity, or short circuit. This battery maintainer is ETL certified for performance and safety. As a small plus, a built-in mounting bracket makes it easy to place the maintainer somewhere convenient when it’s in use.

BLACK+DECKER includes a limited 1-year manufacturer warranty with this product.

Product features:

  • Charges 6- and 12-volt batteries
  • Simply connects using battery clips or O-ring terminals
  • Automatically stops charging and switches to float mode to maintain the battery
  • Overcharging, reverse polarity, and short circuit protection
  • ETL certified
  • Built-in mounting bracket for convenient placement
  • Limited 1-year manufacturer warranty

3. NOCO Genius G3500

noco genius g3500

From popular brand NOCO is the Genius G3500, a 3.5A battery charger and maintainer that works with all types of 6- and 12-volt lead-acid batteries. This versatile all-in-one battery charger and maintainer is ideal for keeping your vehicles fully charged and maintained all year long, especially during long-term storage. It’s extremely easy to use as well, simply plug it in and let the NOCO Genius G3500 take control. The unit will automatically monitor and maintain your car’s battery.

In addition, this product offers an advanced Repair Mode that can help reverse the damaging effects when a battery is left uncharged for an extended period of time. Safety features include sparkproof technology and reverse polarity protection. NOCO provides a 5-year warranty with the Genius G3500.

Product features:

  • 3.5A battery charger/maintainer
  • Works with 6- and 12-volt lead-acid batteries
  • Automatically monitors and maintains your car’s battery
  • Advanced Repair Mode can help reverse damaging effects to uncharged batteries
  • Sparkproof technology and reverse polarity protection
  • 5-year warranty


motopower mp00205a

One of the most affordable options on our list comes from MOTOPOWER with its fully automatic battery charger/maintainer. Designed to charge all types of 12-volt lead-acid batteries, this maintainer features a microprocessor-controlled program that will monitor the entire charging progress and automatically stop once the battery is fully charged. This is when it will start monitoring the battery’s voltage and maintain the battery with a float charging current. Constant Pulse Current Maintenance also aids in making sure the battery doesn’t excessively charge or discharge.

Safety features on this device include overcharge, short circuit, and reverse polarity protections, along with being sparkproof. You can use ring terminals or alligator clips to attach this battery maintainer to your car’s battery. You can also quickly connect and disconnect the maintainer from your car’s battery using the included harness. The device is certified by CE, RoHS, UL, and CEC and comes with a 2-year warranty.

Product features:

  • Charges all types of 12-volt lead-acid batteries
  • Programmed to monitor the entire charging progress
  • Automatically stops and will maintain the battery with a float charging current
  • Overcharge, short circuit, and reverse polarity protections
  • Sparkproof
  • Includes quick connect harness
  • 2-year warranty
Read More Best Car Battery Testers

5. LEICESTERCN LST Battery Charger/Maintainer

leicestercn lst battery charger/maintainer

Another option that works with both 6- and 12-volt batteries comes from LEICESTERCN. This battery maintainer can be used an automatic trickle charger and after it’s done monitoring the whole charging progress, it will automatically switch to float mode. This maintainer also provides visual feedback and diagnostic information, even in maintenance mode, so you can keep an eye on how your battery is doing.

This is an ultra compact and lightweight battery maintainer, which also makes it great for motorcycle owners. This sparkproof device has reverse polarity protection as a safety feature.

LEICESTERCN offers a lifetime quality warranty for its battery maintainer as well as a 12-month refund policy.

Product features:

  • Compatible with 6- and 12-volt batteries
  • Automatic trickle charger that automatically switches to float made for battery maintenance
  • Visual feedback and diagnostic information
  • Ultra compact and lightweight
  • Sparkproof, reverse polarity protection
  • Lifetime quality warranty, 12-month refund policy

6. Optima Digital 400

optima digital 400

Optima is an extremely reputable brand when it comes to automotive batteries, so it’s little surprise the company offers a high-quality battery maintainer. The Optima Digital 400 is designed to automatically maximize battery life and performance, thanks to a built-in battery health mode. This device features a hybrid LED battery-charging gauge with an LCD screen, so you can easily monitor charging progress and maintenance. The company claims the Digital 400 is able to recover deeply discharged batteries that other chargers and maintainers cannot, down to 1.25V.

For convenience, this product can be hooked and tilted thanks to a dual-purpose stand—you can even hang it with the included wall organizer bracket. Advanced safety features include no spark, reverse polarity protection, and the ability to diagnose several battery faults or failures to prevent overcharging. The device is fully automatic and features multi-stage performance charging, conditioning, maintaining, and storage reconditioning mode. Charging is maxed out at 4A.

This battery maintainer is a bit more on the expensive side.

Product features:

  • Reputable brand
  • Built-in battery health mode
  • Hybrid LED battery charging gauge with LCD display
  • Spark-free connection, reverse polarity protection
  • Dual purpose hook and tilt stand design, includes wall organizer bracket
  • 4A max

7. Schumacher SC1299

schumacher sc1299

Schumacher offers a variety of different battery maintainers, depending on the amperage and charge rate you require. Options include 0.75A, 0.8A, 1.5A, 2A, and 3A. These options are powered by a microprocessor that automatically adjusts amperage rate to charge and maintain the battery. Multi-stage charging contributes to precision, safety, and battery life, while reverse hookup protection ensures the charger won’t function if the clamps are reversed.

The more affordable battery maintainers from Schumacher are more basic, with just a charging status LED indicator. Other units have a display with a start/stop interface that is easy to use. Most do have float mode monitoring to ensure an optimum battery charge for maintenance.

Product features:

  • Lineup of offerings (0.75A, 0.8A, 1.5A, 2A, and 3A)
  • Automatically adjusts amperage rate
  • Multi-stage charging
  • Charging status LED indicator
  • Float mode monitoring to ensure optimum battery charge
Read More Best Trickle Chargers

8. BMK Smart Battery Charger/Maintainer

bmk smart battery charger/maintainer

This 5A smart battery charger/maintainer is designed to work with 12-volt batteries and comes from BMK. If you’re using this as a battery maintainer, it’s best to make sure the battery capacity is higher than 15Ah. Constructed from high-quality ABS, this battery charger/maintainer is IP65 waterproof and safety features include short circuit, over voltage, overcharging, overload, and reverse polarity protection. This device also uses Constant Pulse Current Maintenance to avoid overcharge and discharge.

Along with a sparkproof design, using this device is easy thanks to a quick disconnect harness. There is also a built-in 72-hour safety timer, which protects marginal batteries from overcharging.

BMK includes a lifetime quality warranty with its battery charger/maintainer.

Product features:

  • 5A battery charger/maintainer for 12-volt batteries
  • Constructed from high-quality ABS
  • Sparkproof, IP65 waterproof, short circuit, over voltage, overcharging, overload, and reverse polarity protection safety features
  • Constant Pulse Current Maintenance
  • Quick disconnect harness
  • Lifetime quality warranty

9. DieHard 71219

diehard 71219

Another reputable brand on our list is DieHard with its smart battery charger/maintainer. Designed for both 6- and 12-volt batteries, this is a fully automatic, microprocessor-controlled 5-stage charging system with LED indicator lights to show progress. Safety features prevent overcharging and will shut off the device if your clamps are reversed. As a battery maintainer, Float Mode Monitoring will keep your car’s battery at a normal voltage to maintain the battery’s charge.

DieHard includes a 3-year warranty with this specific product, along with a handy quick connect harness. Connection options include 50-amp clamps, a 12-volt accessory plug, or permanently attachable ring connectors.

DieHard also offers more expensive options in the form of a Gold Shelf Charger and a Platinum Shelf Charger, if you need something more heavy duty.

Product features:

  • Designed for both 6- and 12-volt batteries
  • Fully automatic, microprocessor-controlled 5-stage charging system
  • LED indicator lights
  • Overcharging and reverse polarity protection
  • Float Mode Monitoring for battery maintenance
  • Quick connect harness
  • Can use clamps, 12-volt accessory plug, or ring connectors
  • 3-year warranty
Read More Best Portable Car Jump Starters

10. Energizer ENC2A

energizer enc2a

Our last product is also from another reputable battery brand, Energizer. This battery maintainer is designed for 6- and 12-volt lead-acid batteries and is a 7-step, high-frequency smart battery charger that keeps your car’s battery at optimal charge. Like many other recommendations on our list, the Energizer ENC2A automatically switches between charging mode and float mode monitoring.

Simply connect it to your vehicle using the included battery clips or O-ring terminals and let it do its job. Available in 2A, 4A, and 8A variants, this device is ETL listed and safety features include overcharging, reverse polarity, and short circuit protections.

Product features:

  • Reputable brand
  • Designed for 6- and 12-volt lead-acid batteries
  • 7-step, high-frequency smart battery charger
  • Automatically switches between charging mode and float mode monitoring
  • Connects using included battery clips or O-ring terminals
  • Available in 2A, 4A, and 8A options
  • ETL listed
  • Overcharging, reverse polarity, and short circuit protections

What's the Difference Between a Trickle Charger and a Battery Maintainer?

Simply put, a battery maintainer—also known as a float charger—will only turn on and charge your car’s battery when it has self-discharged below a certain threshold. A trickle charger constantly charges your battery, regardless of whether or not your battery is full.

The purpose of a battery maintainer is to keep your car’s battery in good health if it’s sitting inactive for a long period of time, without degrading the battery’s long-term life. Essentially, most maintainers will charge your battery to 100 percent before switching to float mode, where it’ll only resume charging once the battery naturally loses some of its charge.

This means you can keep a battery maintainer hooked up to your car’s battery for a long period of time, without having to worry about it harming the battery.

How do I Choose the Right Battery Maintainer?

As you can tell from our list, many of the popular battery maintainers on the market have similar features. Most options will be capable of fully charging your car’s battery before automatically switching to a maintenance mode, where it will continually monitor the battery’s charge. So how do you choose the right one for you?

Other than shopping by price, you’ll want to check how the company’s customer service is in case your battery maintainer is faulty. Some products on our list are a bit more expensive, but come with impressive long-term warranties. If you need to leave your car sitting in your garage for 3 to 6 months at a time, you’ll want to invest into a high-quality battery maintainer that’s backed by a solid warranty, even if it costs you extra.

We are committed to finding, researching, and recommending the best products. We earn commissions from purchases you make using the retail links in our product reviews. Learn more about how this works.