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Have you ever had that sick feeling when you get in the car to start the engine and it just seems to be lacking power? Especially when you’re away from home somewhere and it’s late at night?

In recent months, I’ve discovered the value of keeping the best solar car battery charger around for just those occasions when I realize my battery power is getting low.

They don’t cost much initially, and they save money – and the environment – long-term, plus they’re safer and more convenient to use than standard chargers.

Quick-Find Best Solar Car Battery Charger Table

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  • Can charge a dead battery
  • Ultra versatile
  • Very efficient
  • Can charge a dead battery
  • Ultra versatile
  • Very efficient
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  • Small and convenient
  • Hangs on your window
  • Tops up battery throughout the day
  • Small and convenient
  • Hangs on your window
  • Tops up battery throughout the day
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  • Small and versatile
  • LED charge indicator
  • Durable
  • Small and versatile
  • LED charge indicator
  • Durable
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  • Waterproof, durable
  • Multiple wattage options
  • Easy to use
  • Waterproof, durable
  • Multiple wattage options
  • Easy to use
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  • Very low profilee
  • Works with a variety of battery types
  • Works well in overcast weather
  • Very low profilee
  • Works with a variety of battery types
  • Works well in overcast weather
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How Do Solar Battery Chargers Work?

A solar panel for charging car battery works off a simple concept, though the details are, of course, more complex. Basically, a solar panel is crafted with charging car batteries in mind and has the proper connectors to use for this purpose.

best solar car battery charging cables

The solar panel itself uses photovoltaic cells – the solar cells – to collect light from the sun and convert it into DC current, or electricity that your car battery can use to charge. They are most effectively used in direct sunlight, though low light and cloudy conditions will still produce some charge.

Solar chargers for automobiles have solar panels on the face which allows you to simply position the panel near a window or in the dashboard to pull in the sunlight during the day.

Some chargers connect directly to the battery while others feed power in via the cigarette lighter or power socket in the car.

What’s the Difference Between a Solar Car Battery Charger and a Regular Charger?

Besides the obvious difference of the power source, the main difference between a solar car battery charger and a regular charger are that standard chargers are more commonly used to fully charge a dead battery.

The other main difference is that a solar charger is far less likely to overcharge your battery and cause damage, though, even with solar chargers, that is possible.

Car battery charger isolated on white

Do Solar Car Battery Chargers Actually Work?

As long as you are using a solar battery car charger for the intended use, yes, they work.

Solar battery chargers do not typically have multiple amperage settings, which means that they only provide a small amount of current to the battery.

This means the solar charger is more beneficial for maintaining a car battery charge than fully charging a battery.

How Long Do They Take to Charge?

Standard solar panels will take anywhere between 4 and 12 hours to receive a full charge.

The average for moderate to high wattage panels is between 6 and 8 hours of direct or mostly bright light charging hours.

During the winter, cloudy weather, or other lower light conditions, the charge time will be closer to the 12 or even 14-hour range.

Do Solar Car Battery Chargers Charge Dead Car Batteries?

A solar car battery charger will not be able to charge a completely dead battery.

They are not for this purpose.

Solar-powered car battery chargers are trickle chargers, meaning they charge at a rate that’s equal to the self-discharge rate. This enables batteries to remain fully charged at the proper level. However, the battery must not be in use when charging as trickle charging cannot keep a battery charged while “in use.”

There may be some models designed specifically for fully recharging a car battery, but these are less common and will use a different form of charging known as float charging.

Understanding Voltage for Car Batteries and Chargers

12-volts is the standard for an automobile battery.

Each battery has six cells with 2.1 voltage. When the battery is fully charged, this equals to 12.6 volts of charge in the battery.

If the voltage in a car battery drops, even that 0.6 down to 12.0, there’s a 75% difference in power. The power drips down from 100% to 25%.

At 12.4 volts, the car battery is charged to 75%, and 12.2 means the voltage is at 50% charged. That means you can consider your battery charged if it is 12.4 volts or higher but discharged and in need of charging again if it’s even 12.39 volts or lower.

You can test your car battery voltage by connecting a voltmeter to the battery.

13.5 to 14.5 volts or more should register while the charging occurs with the car on idle. If it is not producing this, the alternator may be having issues and needs to be tested at an auto parts store.

What are the Benefits of Solar Car Battery Chargers?

There are loads of reasons to use a solar car battery charger instead of a standard wall socket charger. They save money, the environment, and even extend the life of your car battery.

Eco-Friendly Charging

The first thing I’d like to note about using a solar-powered battery charger over the standard electric model is that solar power is eco-friendly.

They use energy harness from sunlight and converted by solar cells into electricity that can charge your car battery.

Solar energy is a far too often overlooked source of renewable energy, but these chargers can help anyone do just a bit better.

Prolong Your Car Battery Health and Life

Solar battery chargers give a steady stream of charging power, even if they don’t deliver the same amount as some of the standard electrically run chargers.

They’re a bit less likely to overcharge your battery, which means they’ll actually prolong the life of your car battery’s lifespan.

Simplicity of Use

A solar car charger is extremely easy to use, which makes it a winner in my book. An elderly person, teenager, or dad with three kids at the heel can grab a 12-volt solar car battery charger and put it to work much easier than a standard electric charger.

You don’t have to figure out amperage and voltage as you do with wall socket chargers. Instead, you just use the charger wherever you are and get going.

Also, because the solar charger doesn’t have as much power behind it as an electrical socket charger has, they’re much safer for beginners to use.

Convenient and Portable

One of the most important things, in my opinion, about a solar automotive battery charger is that it allows you to charge your car battery no matter where you are. Forget to turn the lights off at home? Whip out the charger. Discover the battery’s struggling at a campsite in the woods? Again, just pull it out and charge. You can’t do that just anywhere with a standard charger.

Do note, again, these do not charge completely dead batteries.

Long-Term Savings

Finally, a solar-powered car battery charger may start off as a more expensive charger than standard models, but once you put out that initial cost, you’re done spending.

They don’t require any paid for electrical current to use them, which means you save on electric time after time over the years.

How to Choose the Right Solar Charger

It may seem pretty straight-forward but finding the right solar auto battery charger may prove to be a little tricky if you’re not sure what to look for. If you keep these things in mind, though, you should be good to go on this new territory.

Efficiency in Charging

For the most effective solar-powered battery charger, you’ll want to find one that has an efficiency rating of at least 20%. This efficiency rating means two things.

One, you don’t have to keep these chargers in the direct sunlight all the time in order to harness enough energy to use for charging your car battery.

Two, you can know that you’ll be able to charge your car in low sunlight months – think winter and springtime – or on cloudy days.

Size and Weight

Make sure that the charger you get is a reasonable size and weight for your situation.  They tend to be wide and tall, which is awkward for storage and use in certain car models.

You’ll normally keep your charger in the car in a spot where it will charge in sunlight during the day, so you’ll need a model that’s small enough to comfortably fit in your car.

Or, if you only expect to charge the battery at home, you can choose a larger model as size won’t be as much of a concern.

Portable foldable solar panel battery hanging on the outdoors on a pine tree

Reverse Charge Blocking Diode

When I first saw this term, I was confused. I may know a lot about solar power, but I’m not as familiar with cars. But as I’ve looked into it, this feature immediately became a valuable option that I realized is important.

Reverse charge blocking diodes allow the charger to retain all the energy that it collects throughout the day from the sunlight. It then prevents it from leaking out that energy at night when it’s not in use.

The feature is present in most solar-powered battery chargers, though, so it shouldn’t be too difficult to find. Just make note of a mention of the feature or not, as most manufacturers will include this in the description.

Power

Most solar battery chargers range in power between 2 and 18 volts. The lower the voltage obviously has lower power.

However, they won’t overcharge your battery.

Of course, the higher voltage models will charge your battery much faster than the lower end models.

Unfortunately, a lot of them do not come with overcharge protection so it may be a risky choice going with something higher.

Connectors and Cables

You want to make sure that you get a charger that has more than one 12-volt connector. This gives you multiple connection options.

The length of the power cord will also determine your flexibility with charging by limiting the distance you have for charging if it’s too short.

How We Chose the Chargers for Our Solar Car Battery Charger Review List

Before making this list, I studied up pretty heavily on car batteries, chargers, solar energy, and how they all work together. I wasn’t terribly knowledgeable on the subject of car batteries in particular, but I’ve learned that knowledge is a powerful tool for keeping my family safe.

So, I applied that research and new knowledge to discovering the best solar car battery charger options on the market.

I started out by crafting a list of needs for the standard charger – which helps us know if the charger is worth considering in the first place. Then I went looking for reviews from others on solar chargers for car batteries to see what options are most popular and most highly rated by pro reviewers and real-life users alike.

This search resulted in about 80 different chargers. Obviously, I wasn’t about to review every single one of these, so I hacked down the list by first eliminating any solar car battery charger that didn’t have high enough reviews for me to consider them to be “above average.”

Then I chopped the list down further by looking through the comments and reviews given by real-life users to see what their experiences had been with the various chargers. This knocked the list down to about twenty that seemed worth reviewing.

This list of twenty was then chopped down by doing my own reviews and research into each choice. Below, you have the results of the hours of work put in reviewing and researching the options.

Reviews of the Best Solar Car Battery Chargers

These are the top five absolute best solar car battery chargers on the market.

They’re all easy to install, meet the standards for high-efficiency, reverse charge blocking diodes and others that make them high-quality, durable, eco-friendly, and safe and easy to use for everyone.

#1. Eco-Worthy 20W 12V Solar Panel Kit for Car Batteries (EDITOR’S CHOICE)

ECO-WORTHY 20W 12V IP65 Solar Panel Kit for car batteries review

Overall Rating: 5 out of 5 stars

For a complete kit, the Eco-Worthy 20W 12V Solar Panel Kit for car batteries is your best bet. This is the most versatile option I found while researching and reviewing kits, and so I happily recommend it, along with hundreds of other reviewers/real-life users.

Here’s the breakdown:

  • Charge time: 8 to 12 hours
  • Efficiency rating: high
  • Cables and connectors: yes
  • Voltage: 12V/24V
  • Reverse charge blocking diode: yes
  • Size and weight: 5.4 pounds, 20.5 x 14.4 x0.7inches
  • Wattage: 20W

This is kind of the complete package both in the kit itself and the options and features this solar-powered car battery charger offers.

First off, this charger offers not only trickle charging, but also does float charging – meaning you can charge a dead car battery with it.

It has a nominal output for safety, with overcharge protection and over-discharge protection to keep both you and your battery as safe as possible. It runs with an operating current of 3 amps.

You can purchase this kit with 10, 20, 100, or 200-watt solar panels – though I focused on the 20W option – for getting as much juice as you need. With the right panel at work with the proper off-the-grid converter, you can even run your car’s AC with this charger.

The kit is extremely versatile in that it not only charges your car battery, but it can power a load of other stuff, too, as long as you do so separately.

The solar panel is a high-efficiency polycrystalline panel that’s waterproof to IP65 with a sturdy aluminum frame that lasts for 20+ years.

The kit comes with one pair of 30A battery clips, 6.5-foot extension solar cable, and the solar panel. This is not suitable for batteries with voltage lower than 10.8V.

>> Tap Here to Read More Reviews and See Today’s Price on Amazon.com <<

#2. ALLPOWERS 18V Portable Solar Battery Charger Bundle

ALLPOWERS 18V 5W Portable Solar Car Battery Charger review

Overall Rating: 4.8 out of 5 stars

The ALLPOWERS car battery maintainer and charger uses 5-watts of energy to do a trickle charge of your car battery. It uses a monocrystalline solar panel to draw in power and works for use on any 12-volt battery like those in a car, tractor, boat, motorcycle, or ATV.

Here’s the breakdown:

  • Charge time: 8 to 12 hours
  • Efficiency rating: high
  • Cables and connectors: yes
  • Voltage: 18V
  • Reverse charge blocking diode: yes
  • Size and weight: 11.4 ounces, 12.6 x 5.0 x 0.12-inches
  • Wattage: 5W

The monocrystalline panel works in daylight conditions to charge your car battery and endures moderate weather conditions.

The charger is easy to use, plugs into the cigarette lighter of the car, and tops off the battery whenever needed. You can also connect via alligator clips when needed.

The kit comes with the ALLPOWERS car battery charger, the cigarette lighter plug, suction cups for mounting in the window or dashboard, clip line, alligator clips, and an 18-month warranty.

The solar panel and charger are made of durable ABS plastic and heavy-duty silicone solar cells for durability and easy maintenance.

>> Tap Here to Read More Reviews and See Today’s Price on Amazon.com <<

#3. Sunway Solar Car Battery Charger

Sunway Solar Car Battery Charger 12V Battery Trickle Charger review

Overall Rating: 4.3 out of 5 stars

The Sunway Solar car battery charger is a straight forward, high-efficiency charger that works great for pretty much any outdoor vehicle, ranging from ATVs, snowmobiles, trailers, RVs, motorcycles, boats, cars, and more.

You just slide it into the windshield or dash, attach with the provided suction cups, and you’re good to go.

Here’s the breakdown:

  • Charge time: 8 to 10 hours
  • Efficiency rating: high
  • Cables and connectors: yes
  • Voltage: 15V
  • Reverse charge blocking diode: yes
  • Size and weight: 1.4 pounds, 13.9 x 0.5 x 5 inches
  • Wattage: 3.8W

This solar panel car battery charger comes with a strong, durable cover with ultra-clear PV glass that’s efficient, while the housing is strong, durable ABS plastic.

The charger has an LED light indicator – blinking light – to let you know it’s charging properly, with a blue LED non-blinking light that goes on when fully charged.

This charger comes with the needed suction cups for mounting in the windshield or window and comes with alligator clips, cigarette lighter adapter, and 12-month warranty.

>> Tap Here to Read More Reviews and See Today’s Price on Amazon.com <<

#4. Battery Tender 021-1163 Solar Maintainer with Super Smart Charging Controller

Battery Tender 021-1163 5W Solar Maintainer with Built-in Super Smart Charging Controller review

Overall Rating: 3.8 out of 5 stars

The Battery Tender 021-1163 charger is a super convenient option to use for protecting your battery.

It has a 3-step microcontroller to smartly charge your battery without danger of overcharging. It has reverse polarity protection, is spark-proof, waterproof, and has a built-in temperature compensations sensor. It’s one of the safest solar car battery chargers around.

Here’s the breakdown:

  • Charge time: 8 to 12 hours
  • Efficiency rating: high
  • Cables and connectors: yes
  • Voltage: 12V
  • Reverse charge blocking diode: yes
  • Size and weight: 3 pounds, 14 x 16 x 1-inches
  • Wattage: 5W

The Battery Tender 021-1163 is safe for outdoor use on pretty much any vehicle that uses a 12-volt battery.

It’s built durably to withstand foul weather, plus it’s easy to install, and only gives off nominal charge for safety.

The panel comes in either 5-watts, 10-watts, or 15-watts, depending on your exact needs.

>> Tap Here to Read More Reviews and See Today’s Price on Amazon.com <<

#5. NOCO Black Life BLSolar2 2.5-Watt Charger and Maintainer

NOCO Black Life BLSOLAR2 2.5 Watt Solar Battery Charger and Maintainer review

Overall Rating: 3.5 out of 5 stars

If you’re looking for an ultra low-profile option, the 2.5-watt solar charger from NOCO is a great choice.

Here’s the breakdown:

  • Charge time: 6 to 8 hours
  • Efficiency rating: unknown
  • Cables and connectors: yes
  • Voltage: 12V
  • Reverse charge blocking diode: yes
  • Size and weight: 1.8 pounds, 9.2 x 0.6 x 9.2 inches
  • Wattage: 2.5W

The NOCO 2.5-watt solar charger safely works for a variety of battery types, including wet, gel, MF, EFB, and AGM batteries. That means you’re good to go for charging and maintaining batteries on cars, motorcycles, boats, ATVs, and more.

The NOCO has a thin film technology that works really well in overcast, cloudy, or low light conditions, which makes it perfect for winter time use almost anywhere in the world.

This solar car battery trickle charger can be adapted for use on 6-volt batteries as well, or in battery recovery mode, if the flex regulators are used.

>> Tap Here to Read More Reviews and See Today’s Price on Amazon.com <<

Wrapping It Up

For the best solar car battery charger, you just have to think through a few key factors like efficiency, voltage, wattage, and whether or not the panel comes with the proper cables and connectors needed to charge your car battery.

They’re pretty straight-forward, so go with brands you trust and models that receive high ratings from real-life users.

Just remember that most chargers are not designed to fully charge a dead battery. Solar battery chargers are for maintenance and basic charging instead.

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