If you have that classic car that you only drive during weekends or special occasions, then you are familiar with a battery that has lost its charge.
The battery runs most of the electrical components in the car. However, it needs to be recharged by the alternator – which only happens when you are driving it. If your battery sits idles for a long time then there is a probability that your car will have trouble starting.
Enter battery maintainers. These allow you to keep your batteries charged while preventing overcharging. You can store your battery without worry that it will lose its power. Many people are not familiar with battery maintainers.
This is the reason we have carefully reviewed various products in the market. Here is the list of the best battery maintainers.
Disclaimer – This article may contain affiliate links, this means that at no cost to you, we may receive a small commission for qualifying purchases.
The Best Battery Maintainers in 2021
1. CTEK 56-864 MUS4.3 – Best Value Battery Maintainer
The battery maintainer comes with a small LED screen that informs you of the battery charging status. It is also made to resist various weather conditions and this makes it ideal for use outside. Some of the safety features used include protection from short circuits, sparks, and reversed polarity.
The CTEK maintainer offers more amp at 4.3 compared to others that have 3 amp. This means that you get to charge your batteries faster than the rest. This comes in handy during cold seasons. The maintainer uses an automatic detection system to fully charge discharged batteries, recondition batteries, and it can even detect batteries that have lost their ability to hold a full charge.
- Automatic charging system that uses a patented 8 step process
- Can be used for all weather conditions
- Safety features to protect against reverse polarity and no sparks
- Simple LED lights indicate charging progress
- Offers more amps at 4.3
- Protects against reversed polarity
2.Battery Tender® Plus 021-0128 – Budget Battery Maintainer
This battery maintainer makes it at the top of the list due to its popularity and an incredible 10-year warranty. It offers a 1.25 amp charger. Charging is through a 6 foot AC cord which is long enough to reach your car battery. Included in the package are alligator clips, 1.5 foot DC output cord, battery ring terminals and red/green light condition indicators.
The battery maintainer is temperature compensated. In other words, it regulates itself to ensure that your battery is receiving the right kind of voltage. Once the battery is full, it will automatically change to float mode. The battery tender is compact and portable hence making it one of the most convenient maintainers in the market. To reduce overcharging, the maintainer comes with a smart microprocessor.
Safety features include insulated connector cables and reversed polarity warnings. The only downside to the battery maintainer is that it has low amperage which makes it a herculean task charging a completely dead battery.
- It is fully automatic hence helping the battery maintain a full charge at all times
- 6-foot cord for easy access
- Reverse polarity for enhanced safety
- Comes with alligator clips and battery tender ring terminals
- Reversed polarity warning
- Auto-detects battery condition
3. NOCO Genius G4 Smart Battery Maintainer
Best Multiple Battery Maintainer
If you are one of those people with multiple cars in your garage, you may find the cost of purchasing separate battery maintainers a bit to the higher side. This is where the NOCO Genius G4 comes in. You can charge 4 batteries simultaneously courtesy of 4 banks. The device handles amperage options from 0.75 amp to 26. For enhanced battery protection, the NOCO comes with reverse polarity protection and spark-proof.
Inside the purchase case, you will find connecting terminals, clamps, and extension cables. The device works as both a battery maintainer and charger. It also comes with a 5-year warranty. NOCO Genius G4 can charge both 6 and 12-volt batteries. This is the ideal battery maintainer for those in the automobile service industry.
- Offers four banks for charging four batteries
- Handles 6 and 12 volts batteries
- You can vary the amperage from 0.75 to 26 amps
- 5-year warranty
- Reverse polarity for safety
- Offers intuitive diagnostic information
- Useful accessories
4. Schumacher SP1297 Battery Maintainer
This battery maintainer comes with an intuitive LED screen that informs you of the charging process. You can use it to charge both 6V and 12V batteries. The microprocessor is found inside a durable case and it comes with two sets of insulation cables – one for car batteries and the other for charging smaller batteries. It also comes with a convenient hook attachment which saves you space as you can hang it with your other tools
The SP1297 handles 3-amp charge and with the multi-charging feature, your batteries are protected from overcharging. With a float mode monitoring system, it will detect any drop in charge and top it up automatically. This ensures that your battery is fully charged at all times. For safety, it comes with a reverse hookup detection feature.
- Multi-stage and multiprocessor controlled battery maintainer
- Float mode monitor for optimal battery charge
- Comes with the hook attachment for enhanced storage
- Sturdy and well-maintained case
- Auto-detects for 6V and 12V batteries
- Intuitive LED display
5. Optima Digital 400 12V Digital Battery Maintainer
This battery maintainer handles 4 amp and comes with an intuitive LCD display that informs you of the charge status. You can store the maintainer through a simple hook and stand. It also offers a spark-free connection technology.
The Optima Digital works as both a battery maintainer and charger. It can be used for marine and motorcycle batteries. The device manufacturers claim that the battery maintainer is able to recover the charge lost.
- Recovers charge from batteries that are down 1.25V
- Dual-purpose hook
- Hybrid LED display
- Spark free technology
- Can be used in motorcycles automobiles
- Automatically maximizes battery life
6. Schumacher SC1319 Battery Maintainer
Not all battery maintainers in the market are meant for cars. Some like the Schumacher SC1319 is ideal for small batteries found in boats, motorcycles, and power sports. The amp is low at 1.5 amps meaning you will spend a considerable amount of time recharging your 6V and 12V batteries.
The battery charger comes with insulated clamps that protect your hands from shock. In addition, it has an auto-detection mechanism that detects battery damage.
The Schumacher is multi-stage and microprocessor-controlled for enhanced precision and safety. Should you mess up with the clamp connections, there is the reverse hook-up feature that prevents the charger from even charging until the clamps are placed right.
- Offers 1.5A to handle 6V to 12V batteries
- Auto voltage detection
- Reverse hook-up protection
- Ideal for small batteries
- Insulated clamps
- Microprocessor controlled for extra safety
7. NOCO Genius G3500 Battery Maintainer
This battery charger comes in innovative design and is praised for leading in safety features. The housing is sturdy enough to protect the internal elements of the charger from damage. It also has an LED screen that offers information concerning battery-charging status. Some of the safety features that stand out include over-charging protection, reversed polarity, and spark-proof design. All these features are added to ensure that your battery charger lasts a lifetime.
The NOCO Genius has a microprocessor that automatically detects the type of battery used and the amount of power needed to bring it to a full charge. You can use it to charge your lawnmowers, motorboats, ATVs, and cars. The multi-charging system handles all batteries of 6V and 12V. Included in the purchase price are battery terminal eyelets, 12V car accessory port connector, 10-foot extension cord, and standard clamp connectors.
- Simple Plug and play installation
- Works with all kinds of 6V and 12V lead-acid batteries
- Advanced repair mode protects batteries from damage
- Safety features like spark proof and reverse polarity protection
- Advanced charging technology protects against over-charging
- Useful accessories
8. DieHard 71239 Platinum Battery Maintainer
From the name you can deduce that this battery maintainer is packed to keep your batteries charged for long. It charges both your 6V and 12V drained batteries. Detection of the type of battery and charge amount is through an internal microprocessor. It also has a user-friendly LED screen that keeps you informed on the charging process and when to connect the clamps.
The DieHard 71239 runs on 3 amp and which means it will take some time to fully charge your 12V battery. To prevent any instances of overcharging it comes with a multi-stage charging system. Once you purchase the device, you will get additional ring connectors for long-term installation, battery connector cables, and a single cable for connecting with your car’s 12V accessory outlet.
- The device will automatically detect 6V or 12V and measure the charge for each
- Offers multi-stage 6/12V 3A charging
- Digital messaging prompts inform you of the status of charge
- Prevents overcharging
- Allows multiple battery charging
- Comes with various charging accessories
9. Schumacher SC1300 Battery Maintainer
We have seen a lot of Schumacher products on our list but it is because the company has gone out of its way to producing quality products. This version is meant for small batteries courtesy of its 1.5 amp charging speed. While it works well for small batteries it will take longer to fully charge a 12V battery. The battery maintainer comes with a one year warranty and a host of features that you will find in the high-end models.
For battery protection, the Schumacher SC1300 comes with auto voltage protection, float mode monitoring, reverse hook-up protection and automatic adjustment of the amp to reflect the charge. At any point during the charging process, you are able to view the process through the LED lights. While the device is affordable, the materials used for construction are high quality and have passed stringent DOE compliance. The battery is small enough to fit in small spaces in your garage but lacks the hanging hooks common with some top-rated models. Instead, you have small holes that you can make hanging modifications with.
- The microprocessor will automatically adjust amperage
- Safety features like float mode monitoring, auto-voltage detection, and reverse hookup protection
- Reverse polarity protection
- The plastic casing protects against oil, gasoline, and water
- Small design that fits in the garage
- Multi-stage charging
10. Battery Tender 022-0185G-dl-wh Battery Maintainer
Another battery tender product makes it no our list. This has become one of the most popular battery maintainers online with lots of positive customer reviews. It has the bragging rights to do so. For one you are getting a battery maintainer that has both a robust design, combined with affordability. The designers have not compromised on anything that you find in other top battery maintainers.
With some little patience, you should use the 1.5 amp battery to take your 12V to full charge. The charging system is four-stage and it is fully automatic. This means the battery maintainer will easily recognize a 6V from a 12V battery. You can use the device on your car’s battery, ATV, lawnmowers, jet ski, and other sports equipment. Some of the safety features that stand out include the safety timer, reversed polarity detection, and insulated connector clamps.
The battery tender is a lightweight device that makes it easy to carry around the garage. Its plastic casing is also resistant to destruction from weather elements. This is an ideal battery charger for those doing light battery maintenance work.
- Allows you to automatically switch from full to float charging mode
- Safety features include reverse polarity protection and red/green warning lights
- California compliant charger
- Features 4-step charging program
- Portable design for easy storage
- Handles most batteries
Factors to consider when purchasing a battery maintainer
Since the battery maintainer is expensive equipment, you need to be careful in your selection process. Battery maintainers are life savers when it comes to reviving dead batteries. If you have more than one car, there are instances when you use one at the expense of the other. When your battery loses charge you can either jump start it or have a battery maintainer that restores the charge.
When your battery is down, you need to restore its charge as fast as possible. An amperage is a unit of measure that records how much current is going into the battery. The higher the amp the faster it is to charge the battery. However, new innovations in battery maintainers have led some to come with various charging modes that maximize charging. As you consider the amp, also factor in the charging cables. These should be insulated to protect charging.
Since you are dealing with voltage it is imperative that you put into consideration various safety features like short circuit protection, auto voltage, reverse polarity, and spark resistant clamps. Higher-end models will come with LED screens that give you more information as to the status of the battery. You will also be informed in case of over and undercharging.
Difference between trickles and maintainers
The main difference between the two is that a trickle will apply a constant charge to the battery despite the battery being fully charged or not. If you do not disconnect the trickle then you may end up ruining your battery. On the other hand, the battery maintainers will restore your battery charge but once it is full, it will revert into float mode. In this instance, any drop in voltage will automatically be topped up.
Some of the battery chargers can either handle 6V or 12V. If you have multiple batteries it would be prudent to get one that handles both. In addition, there several battery maintainers that can handle up to four separate batteries. All the batteries charge independently and concurrently.
Not all batteries are the same. Most cars use typical acid-lead batteries. However, it is prudent that you identify a battery maintainer that can handle a variety of battery types. This means you can use it for your car, truck, and other automobile classes.
Roles played by Battery Maintainers
Battery maintainers often perform more than one function. Your needs will determine the type that you get. Some of the roles that the battery maintenance fulfills include:
- Battery charger: Maintainers are primarily battery chargers. In this case, if you have not been using for some time it will drop in voltage. Charging your battery restores it back to its original state. The downside is that battery charging is a slow process.
- Battery boosters: If you have a completely dead battery, a battery booster will restore the charge fast. Most car owners will keep battery boosters for emergency purposes.
- Diagnostic functions: Some battery maintainers will come with diagnostic functions that check whether your battery is in good condition. In case of any problems, this will displayed on the screen.
Battery Maintainer FAQ
How long does it take to fully charge a car battery with a battery maintainer?
How long it takes to fully charge a battery will depend on the amp of the battery maintainer. A typical car battery will require 48 amp to be fully charged. Assuming that you are using a 4 amp charger it will take you roughly 12 hours. However, there are charger boosters that can give you more charges at a faster rate.
Can you revive a dead battery?
Your car battery plays a vital role in powering most of the car’s electrical components. The car’s alternator will keep the battery recharged when you are driving. However, if you do not use your car frequently it will drain off all its power and you will find trouble starting your car. Battery maintainers are designed to keep your car’s battery fully charged when not in use. The chargers are capable of recharging a battery to full.
Can I leave my battery to charge overnight?
With lead-acid car batteries there is no problem with leaving them overnight to regain their charge. Most battery maintainers have security features that protect your battery from overcharging. You should also note that the battery chargers run on between 1.5 amp and 4 amp, this means it will take you more than 24 hours to fully charge your battery.
What are the benefits of using battery float chargers?
The main benefit of using the float chargers is to keep your battery fully charged at all times. In this case, you do not need to wake up in the morning and start looking for jumper cables. Some people have multiple cars –with one car being used for special occasions. If you do not want to keep jump-starting your car then invest in float chargers. More advanced models can even charge multiple batteries simultaneously.
How do I charge my battery at home?
Battery maintainers have eliminated the need to take your dead battery to an auto repair shop for recharging. They are versatile, easy to use and portable. To use them, first, connect the charger to the electric socket outlet. Most of the devices in the market come with insulated cables that you connect to the battery terminals. Once the clamp is securely in place, you can turn on the charger and select your preferred voltage. Check the LCD/LED displays that everything is working fine and leave the charger for several hours to charge. With safety features, some of the chargers will disconnect charging when the battery is fully charged.
Is it possible to overcharge a car battery?
When there is the risk of overcharging a battery the sulfuric acid inside will boil and mix with the distilled water. If you touch the outer casing of the battery you will notice that it is very hot. In extreme circumstances, it will begin to melt. All this can be avoided by getting a battery charger that has an overcharging mechanism. This will cut the current when the battery is full.
Nothing is irritating to a car owner than the need to start looking for jumper cables early in the morning while you should be rushing to work. However, with the right battery maintainer, this could be a thing in the past. In this review, we have identified the Battery Tender® Plus 021-0128 as the best battery maintainer. Firstly, the 10-year warranty is simply great and it comes with a host of connecting accessories. It automatically detects the type of battery and has a safety feature to prevent overcharging.
Hi, I’m Magnus, the owner and the writer of Mechanic Base. I have been working with cars for 10 years, specialized in diagnostics and troubleshooting. I created this blog because I was tired of finding false information on the web while looking for repair information. I hope you enjoy my content!