Best 12v Battery Charger – Fully Automatic Booster Starter

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Modern RV engines are marvels of engineering perfection, with durability, performance, and reliability that are unmatched by past examples. Without a charged and ready battery to start it all up though, you’ll be caught out with a cold engine and no way to get moving. Battery chargers are there to help you properly condition and maintain your RVs battery and help you get moving again when there are problems. Today we’re going to help you find the best 12V battery charger to keep your RV in tip top shape.

Best 12V Battery Charger

When we talk about 12V battery chargers there are two devices we mean. The first are wall plugged tools meant to top up and maintain your RV’s battery during storage.

They provide a float charge that keeps your batteries healthy and your RV ready to go. The second are portable battery chargers that double as emergency jump starters.

They incorporate battery charging gear with a built-in battery pack to keep you moving no matter where you find yourself.

Our list includes both types of 12V battery chargers, with excellent examples of each across a range of price points and performance levels.

Battery Tender 12 Volt Junior Automatic Battery Charger

Battery Tender 12v Charger

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The Battery Tender Junior is a 12V automatic battery most suited for use as a battery maintainer. It plugs right into a standard 110V AC wall outlet and outputs .75A/750mA of 12V power.

That’s technically enough to charge up a battery, but it’s going to be a really slow charge. For a pretty modestly sized 80Ah 12V battery it would take nearly four full days to charge.

As a maintainer though it excels. It provides an automatically triggered float mode with just the right current. This allows you to leave your RV stored pretty much indefinitely without fear that your starter battery or battery bank will be depleted.

So long as you’re aware of its limitations the Battery Tender Junior is an affordable and effective 12V battery charger.

NOCO Genius 5 Fully-Automatic 6V And 12V Battery Charger

Noco Genius 12v Battery Charger

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The NOCO Genius 5 is an automatic 6V/12V battery charger packed full of really advanced features. It’s designed to function as a battery charger, maintainer, trickle charger, and battery desulfator.

That’s a lot of hats for a single charger to wear, but the Genius 5 comes through when it counts. It’s capable of providing up to 5A and can intelligently charge all kinds of lead-acid and lithium-ion batteries.

The Genius 5 automatically reads the state, voltage, and current strength of your battery and goes to work. It even adjusts the rate of charge to the optimal possible for the ambient temperature.

If you’re looking for a reliable and reasonably priced battery charger that can do it all, look no further than the NOCO Genius 5.

BLACK+DECKER BM3B Fully Automatic 6V/12V Battery Charger

Black + Decker Fully Automatic 12 Volt Charger

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The Black + Decker BM3B is a 6V/12V automatic battery charger optimized for battery maintenance. It uses an intelligent charging system to provide the best possible float charge for your RV or vehicle battery while in storage.

It’s quite compact at just under 10 inches long, and has a built in mounting bracket to make placement easier and more secure. It works on all types of lead-acid batteries and includes the most in-demand safety features.

You can use the BM3B to maintain your batteries with full confidence that they’ll be taken care of. You can also use it as a way to charge up smaller batteries on things like motorcycles or snowmobiles.

If you’re looking for an inexpensive and reliable battery maintainer for your lead-acid batteries the Black + Decker BM3B will get the job done.

Schumacher SP1356 6V/12V Fully Automatic Battery Charger

Schumacher 12v Fully Automatic Battery Charger

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The Schumacher SP1356 is a 6V/12V automatic battery charger designed for charging and maintaining lead-acid batteries. It offers up to 3A of charge and includes an intelligent float charging mode.

It comes standard with both clamp style and ring style connectors. This gives you the option of charging up a low battery quickly or setting up a more permanent connection for battery maintenance.

The SP1356 incorporates the most important safety features and has an easy to ready digital display. This makes it much easier to get started charging and allows you to see at a glance that everything’s alright.

For effective long-term battery maintenance on your RV or stored vehicle the SP1356 offers an effective solution.

BEATIT G18 2000Amp Peak 12V Portable Battery Charger

Beatit 12v Portable Battery Charger

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The BEATIT G18 is a portable battery charger designed to act as a backup jump starter in case your RV or vehicle battery runs dry. It uses a 21,000mAh battery pack that’s capable of providing a surge of 2000 amps power to start up your RV.

The G18 doesn’t just start your car though. It can also top up your cell phone or act as an emergency flashlight in a pinch. It makes it possible to ensure you have communications and visibility even in trying conditions.

Keeping the G18 in a compartment of your RV gives you extra peace of mind. No matter how remote your camping is you’ll always be able to start up your RV and get on the move.

If you’re looking for a reliable RV jump starter that doubles as a backup 12V battery charger you can definitely do worse than the BEATIT G18.

DBPOWER Portable Car Charger

DBpower Portable 12v Battery Booster

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The DBPOWER portable car charger is a jump starter designed for cars and medium sized RVs. It’s capable of providing up to 800A to jump start gas and diesel engines.

It does this with an 18,000mAh lithium-ion battery chargeable via and included power cord. That’s just the tip of the iceberg where its capabilities lie though.

The DBPOWER can charge your phone through a pair of USB ports or act as an emergency flashlight. It even has a built-in compass for serious emergencies.

If you’ve got an RV with an engine capacity less than 5.5L the DBPOWER portable battery charger is a great and reasonably priced option to prepare for dead batteries.

TACKLIFE T8 12V Auto Battery Booster

Tacklife 12v Auto Battery Booster

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The TACKLIFE T8 is a 12V battery booster sized for cars, trucks, SUVs, and small to medium RVs. It does this with an internal 18,000mAh lithium-ion battery pack capable of starting up your vehicles as many as 30 times in between charges.

That may sound really similar to some of the other portable 12V battery chargers on our list but the T8 adds a few little twists. It has a manual on/off switch that vastly reduces the power loss in storage.

It can sit for as long as 12 months without being charged and still reliably start up your vehicle. It also offers a pair of USB ports plus an adapter that gives you a spare 12V cigarette style outlet.

That makes it easy to power 12V appliances and devices like vacuums and air compressors.

All in all the TACKLIFE T8 is a feature packed portable charger available at a competitive price. If you’re looking to add an emergency jump starter to your RV setup it’s a good choice.

NEXPOW Q9B 12V Auto Battery Booster Pack

Nexpow 12v Auto Battery Booster Pack

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The NEXPOW 12V Auto Battery Booster Pack is a portable jump starter designed for use with large gas and diesel engines. It can offer up to 2,500A of peak current to get everything from heavy-duty trucks to Class A motorhomes.

It has a 22,000mAh lithium-ion battery designed to hold a charge in storage. It’s good for about three months between charges and offers some really useful features besides just starting up your RV.

One of the first things we noticed about the Q9B was how it charges. It uses an advanced USB type-C port, allowing you to charge it up from a wide variety of different cords including some computer chargers.

Under the hood it incorporates an advanced QDSP charge control chip. It allows it to reliably start up your engine even under challenging conditions like extreme cold.

Overall the NEXPOW Q9B is a durable and highly portable 12V battery charger. It’s capable of starting up every type of RV and has enough storage life to keep your engine running no matter where you end up.

TOPVISION 12V Portable Auto Battery Charger

Topvision 12v Battery Starter

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The TOPVISION 12V portable battery charger offers multi start performance for RVers who always want to be prepared. It provides up to 2,200 peak amps from a 20,900mAh lithium-ion battery pack.

It’s designed to provide up to 50 jump starts from a single charge and to hold its charge for longer periods in storage. It incorporates all the most important safety features including things like short circuit protection, over current protection, and reverse polarity protection.

The TOPVISION also offers a pair of USB ports plus an LED flashlight. It allows you to charge up essential devices during an emergency and gives you light to work with while trying to hook everything up.

The TOPVISION portable battery charger is compact, easy to store, and competitively priced. It gives you good performance when it counts and offers some extra features we appreciate.

Buyers Guide to Buying the Best 12V Battery Charger

When it comes to picking out the best 12V battery charger there are a few key factors to look at. These help determine what kind of charger you need and the level of performance you can expect.

Price

12V battery chargers are very affordable. Wall plug models designed to maintain and condition batteries rarely cost over $30 with portable battery chargers a bit more expensive.

You can still get a great emergency jump starter for well under $100.

Portability – Size and Weight

Up until just a few years ago, anyone looking for a 12V battery charger would have meant a wall plug unit meant for charging depleted car batteries. All that changed with the introduction of portable 12V battery chargers.

These combine the same intelligent charging systems of traditional battery chargers with their own (usually lithium-ion) battery pack. They’re marketed as car jump starters, portable chargers, and many other terms but all fulfill basically the same role.

These are quite small, though fairly heavy. This is due to their internal batteries which are pretty much always hefty. The best models are strong enough to jump-start a car, SUV, or even RV yet small enough to fit into a glove box.

We highly recommend every RVer keep one with them, and that they periodically check them for a full charge. It’s a serious reassurance to know you’ll always be able to start up your RV.

Even though wall plug 12V chargers aren’t technically portable in how they’re used, they are far more portable than they once were. A while back you had to basically wheel a battery charger out on its own cart. Now they’re about the size of a bottle of soda and weight just a few pounds.

Indicators and Display

Old school battery chargers weren’t the easiest things for the layman to use. At most you would get a gauge or two that would tell you a little bit about how much power it was providing and at what voltage.

Thankfully those days are well behind us. Modern 12V battery chargers range from those with simple lighted indicators all the way up to comprehensive digital displays.

These provide you with accurate information on charge rate, voltage, amperage, and several other important metrics.

Power

For a 12V battery charger power comes down to voltage and amperage. Voltage determines what kind of batteries it can charge and amperage controls how quickly it can charge them.

Most larger DC batteries like those found in solar power systems run between 3V and 24V. You need a battery charger that’s compatible with your battery bank.

Amperage shows how many amps a battery charger is capable of providing an hour. Most smaller maintenance and trickle chargers provide between .25A and 2A.

As you get into larger and more capable battery chargers it’s not unusual to see units with 20A+ capacity.

Safety

Anytime you’re working with electricity safety should be your number one priority. Good 12V battery chargers have safety features baked right into the bones of the device.

A few that you should look for include:

  • Reverse Polarity Sensor/Alarm
  • Spark Proof/Resistant Clamps
  • Float Mode
  • Clamp Amps
  • Battery Tester

The reverse polarity alarm, spark-proof clamps, and clamp amps both apply to the physical application of the clamps. The reverse polarity sensor alerts you if you’ve got the clamps on the wrong terminal of the battery.

If you turn it on with the clamps on the wrong terminal it can be a Very Bad Thing. The spark-proof clamps prevent sparking when putting live clamps onto a terminal. The clamp amps is a sensor that feeds you important information about the current flowing within the battery.

Float mode refers to a low powered charging mode designed to maintain the charge on a battery. If you’re using a 12V battery maintainer you want one with an effective and reliable float to protect your battery from damage.

Lastly, you always want a battery tester included in your charger where possible. They allow the battery charger itself to determine exactly at what rate and power to charge your battery. It can also help prevent things like overcharging or attempting to charge a truly dead battery.

Automatic, Manual or Solar

When it comes to true 12V battery chargers there are three main varieties: Automatic, manual, and solar. There are pros and cons to each variety, with some fulfilling specific roles better than others.

Manual chargers are the most basic and perform the least complicated role. If you hook a manual charger up to your battery it will charge it at a continuous rate.

Manual chargers are cheap, reliable, and pretty much indestructible, but they do have a big flaw. If you don’t monitor the voltage of your battery consistently it’s easy to overcharge them with a manual charger.

Solar chargers are much newer and rely on a small solar panel that connects to your battery. They provide the lowest amount of power for any of the 12V battery chargers but still serve a very important role when used properly.

While solar chargers are slow to charge, they don’t require any source of power other than sunlight. They’re ideal as trickle chargers or battery maintenance tools for RVs or other vehicles that you’re storing away for a season.

Lastly, we come to the automatic battery chargers. These bad boys combine powerful charging capability with an intelligent voltage and amperage monitoring system.

It allows them to adjust the rate of charge and total power provided as the battery charges up. You can hook an automatic charger up to a car battery and leave it alone for a week then come back without fear of an overcharged battery.

Pretty much the only downside to an automatic charger is the price. They’re more expensive than manual battery chargers, though prices have been dropping rapidly.

Final Thoughts

Picking out the best 12V battery charger for your situation requires only that you know your needs.

If you want to maintain and condition your battery choose from one of our excellent wall plug 12V battery chargers.

If you’re looking for an emergency backup while you’re out on the road, a portable 12V battery charger is the way to go.

About Karan Riley

I am the owner and main contributor to RV4Campers. I first got bit by the RVing bug when I joined a friend who was into Van Life for weekend getaways. It became apparent very quickly that this was a style of life I enjoyed and wanted more of, so it wasn't long before I had my own travel trailer. I didn't have a lot of money to throw around back then so I did lots of research into all the gear and gadgets. And this is how my RV passion exploded, I've now spent countless hours playing around with many different bits of kit and reading user manuals. And it's this wealth of knowledge I bring to RV4Campers.