The 8 best solar battery chargers for your car, phone, boat, RV, and more!
Using a solar battery charger is an easy way to keep your vehicle’s battery, your phone, or even laptop juiced up and ready to go. The beauty of a solar battery charger is the simplicity and ease of use just about anywhere with sun. A solar battery charger will include a solar panel, as well as wires to connect the solar panel to your battery or device. Some kits can also include a few additional tech items like charge controllers and blocking diodes (more on those later).
In most cases just put the solar panel in the sun and connect your battery. It’s that easy.
Before we move on, here’s an important distinction. Solar chargers for 12 volt applications like cars, RVs, and boats are designed to only maintain your battery’s charge when not in use. These small solar chargers aren’t big enough to fully charge dead batteries, so instead they just trickle charge the battery, ensuring they’re always ready for your next adventure.
Solar chargers for smartphones and tablets, however, produce the 5 volts your iPhone actually needs to recharge after a complete discharge.
Needless to say, solar chargers for vehicles and smartphones are quite different, and are NOT interchangeable. However, we include them all here, as most of us collectively refer to all of it as solar battery chargers.
We searched and searched for the best solar chargers available this year and focused in on eight products in eight different categories, laid out below. All the solar chargers we’ve included are cost-competitive, durable, and backed up with great customer service.
Of course, some are more expensive than others, but if they are, we’ve laid out exactly why you’d want to spend that extra cash. After taking a look at these sweet products, we think you’ll agree!
Top 8 Best Solar Battery Chargers in 2021
- Battery Tender Solar Charger – Best for Car
- DuraVolt 20W Marine Solar Battery Charger – Best for Boat
- DuraVolt Magnetic Battery Maintainer – Best for RV
- POWOXI Solar Battery Charger – Best for Motorcycle
- BigBlue 28W Solar Charger – Best for Phones
- Voltaic Systems Arc 20 Rapid Solar Laptop Charger – Best for Laptops
- Renogy E.FLEX 10W Ultra Thin Solar Charger – Best for Backpacking
- Energizer PowerKeep – Best for Rechargeable Batteries
Solar Battery Charger Reviews
Read on to learn more about each of the best solar charger companies on our list to find the perfect one for your battery or devices.
Ready? Let’s get to it!
If you’re looking for a well-built, leave-it-and-forget it solar battery maintainer for your car, Battery Tender’s Solar Charger is the perfect solution. It’s heavy-duty, waterproof, and comes with everything you need to keep your battery topped up with free, clean energy.
Battery Tender’s been around for ages and you can find their products online and in person at stores like Walmart and local auto parts store. On Amazon, you can find their Solar Charger in 5, 10, and 15 watts. Each comes with alligator clips to attach to your battery, but not much else.
It’s waterproof, so you can leave it outside, but remember it’s quite large – the 15 watt panel is over 3 feet long and a foot wide! However, it’s got some great features that set it apart from almost every other solar charge controller out there.
First, Battery Tender’s Solar Charger includes a built-in charge controller to protect your battery from over-charging and possibly suffering from premature death.
Almost all other solar chargers don’t include a controller, leaving you to hope you never have any issues or forced to buy one more piece of equipment for your solar battery charge system. Some manufacturers and/or users argue that including a charge controller on solar panels this small is overkill, but it certainly takes all the worry away wondering whether you should use one, since you’ve already got it.
Second, Battery Tender also includes an integrated blocking diode in their solar chargers. Without a blocking diode, your battery can actually leach electricity to your solar panel at night, leading to a dead battery. If you don’t have a blocking diode in your solar charger, you have to disconnect your battery from your solar charger every night.
People use these solar chargers for all sorts of vehicles: boats, RVs, cars and trucks, and camper trailers. Some even permanently mount the solar charger to the front of their camper trailer. Customers confirm the charger’s great performance stats and noted that, even though the chargers are quite large, they’re lightweight and easy to maneuver.
If you’re looking to keep your car topped up, you can simply place the solar panel on your dash and let the sunlight do its work.
Bottom Line: Battery Tender’s Solar Charger is a bit more expensive than others on our list, but you get an integrated charge controller and blocking diode. Even though it’s larger than others on our list, with these nice additions you don’t have to worry about your car’s battery. It’s one of the safest, easiest chargers to use.Learn More & Buy Now at Amazon
The DuraVolt 20W Marine Solar Battery Charger tops our list for the best solar battery charger for boats. Solar panel manufacturer ITC Solar originally manufactured their DuraVolt solar panels to power high-tech buoys designed to monitor water quality in Tasman Bay in New Zealand. Realizing recreational boaters and other industries could benefit from these small, durable solar panels, they branded them as DuraVolt and now you can find them on Amazon.
These solar chargers are semi-flexible and covered in a plastic film and aluminum backing. The solar charger is wrapped in a heavy duty rubber gasket with a mounting hole in each corner. Their 20 watt solar charger is quite small, at 14” x 16” and just 1/4” thick.
The solar chargers come pre-installed with an SAE output plug, as well as alligator clips, battery terminals, and a lighter adapter so you can charge your boat in whatever manner is easiest.
An important note: The charger doesn’t come with a blocking diode or charge controller.
DuraVolt claims that electricity loss is so little thanks to their solar panels’ high-quality internal components that a blocking diode is unnecessary, though they’ll send you one for free if requested. Also, a handful of buyers have installed blocking diodes or kill switches themselves to avoid any potential issues.
DuraVolt also notes that their 12v chargers don’t need a charge controller, as they use self-regulating panels with a lower operating voltage than other 12v solar panels. A handful of buyers still use a charge controller, but the manufacturer notes it’s not necessary thanks to this low voltage.
Many buyers permanently attach the charger to the deck or T-top and use it to keep the battery topped up when moored or when out on the boat during the day.
Customers continually praise the charger’s simplicity and toughness. All you have to do is bolt it down, put on the right adapter, and connect it to your battery.
Bottom Line: The DuraVolt 20W Marine Solar Battery Charger is the perfect option for your boat or any other intense setting where ruggedness and dependability is key – and water is imminent.Learn More & Buy Now at Amazon
We looked at DuraVolt’s Marine Solar Charger above, but their solar chargers are not just for boats. DuraVolt also manufacturers a magnetic solar charger based around the same extremely rugged solar panel as their marine products.
Their Magnetic Battery Maintainer is specifically designed for fifth wheel and camper trailers. The 8.3 watt solar panel has an extremely powerful magnetic back that sticks to any surface, including your fifth wheel’s hitch or even the hood of your vehicle.
DuraVolt uses neodymium magnets, the strongest magnet on the market, for these chargers. Many users note that, while skeptical initially of the strength of the magnet, they don’t move an inch even after high speeds and bumpy roads. This makes DuraVolt’s magnetic solar panel – quite literally – the easiest installation of all the chargers on our list!
Just like DuraVolt’s marine charger above, this solar panel is covered in a semi-flexible plastic film and aluminum backing for maximum durability, while also making the solar panel incredibly light. It’s 12” x 10”, just a ¼” thick, and weighs 1.9 pounds. As the solar panel is semi flexible, it can flex to the curve of your vehicle’s hood or any other metal, ‘gently curved’ surface.
The charger includes a 10 foot cord that ends with an SAE output as well as alligator clips and battery terminal adapters.
DuraVolt claims their solar battery chargers do not need a blocking diode or charge controller, thanks to their unique design and quality components. Some buyers choose to add one or the other, or both, after buying the kit, but most seem to just install what’s included without any additions and report the charger still works great.
DuraVolt customers typically have two things to say about the company. First, their solar panels are incredibly durable. You’ll certainly pay more for them, but you’ll also know your RV’s battery will always be ready to go. Second, DuraVolt’s customer service is excellent. Wait time is short, there’s no long phone prompt menu, and the employees are knowledgeable.
Bottom Line: DuraVolt’s Magnetic Battery Maintainer might be more expensive than other similarly-sized battery chargers, but it’s easy to install, extremely rugged, and backed up by excellent customer service.Learn More & Buy Now at Amazon
Keeping your motorcycle battery topped up in the off-season is easy with POWOXI’s 3.3 watt solar charger that is compact, 100% waterproof
The charger uses amorphous silicon solar cells, which perform well in low-light conditions. At 3.3 watts, you should have more than enough power to keep your bike’s battery charged up. The solar panel is encased within UV-resistant ABS plastic and includes mounting holes in each corner, along with suction cups to mount the panel.
The charger itself is 14” x 8.5” and just under an inch thick. This small size and the low weight of just 2.2 pounds makes this charger extremely portable and easy to set up. It includes a 10’ cord ending in an SAE output, with alligator clips and a cigarette lighter adapter (if you want to charge a vehicle).
POWOXI also integrates a blocking diode into the charger, so you’re able to leave the charger connected to the battery 24/7 without fear of damaging it (read more on blocking diodes at the end of this article).
The solar panel also includes a small blue LED light right on the front which flashes when its charging your battery – a nice little touch that allows you quickly keep tabs on your battery’s current state of affairs.
This kit doesn’t come with a charge controller, but most experts agree that any 12v solar kit under 5 watts doesn’t need a controller, so you should be good to go without one.
Of course, this solar charger isn’t just for motorcycles. Customers report using this little battery charger for jet skis, RVs, trucks, and cars. And many report it works great in low light, cold weather, and extreme heat – exactly what you want to hear for an all-weather, outdoors solar charger.
If you want to shave some costs, you’ve got a couple options. Fist, POWOXI also manufactures a monocrystalline version of this same solar charger for a bit less. It won’t produce as much electricity in low light conditions, but if you’re just going to connec the charger and leave it for a full season, it’ll work just fine and save you a few bucks.
If 3.3 watts is still too big for your needs, POWOXI also manufactures a smaller 1.8 watt version at about half the price, so take a look at that one if funds are low.
Bottom Line: POWOXI’s solar battery charger is low-cost, compact, and easy to set up, perfect for winter when your motorcycle is covered.Learn More & Buy Now at Amazon
BigBlue’s 5 volt, 28 watt solar chargers packs a punch big enough to charge your iPhone, iPad, Samsung Galaxy, DSLR, or any other 5v gadget. It actually uses Sunpower solar panels, some of the most efficient solar panels currently available! Needless to say, it’s a quality item and they’ve done their work to make it such.
The charger comes with 2 USB ports, providing up to 2.4 amps per port, with a max of 4 amps overall. The charger includes some tech that detects your connected devices to charge each in the fastest method.
Some solar chargers have a hard time restarting after shade or rain block sunlight and the solar panels stop producing energy.
With these products, users have to unplug their devices to jolt the device into working again. BigBlue though has solved the issue by including a chip that automatically pauses charging when shaded, then restarts when sunlight is available again. Needless to say, this allows you to not worry about your charging and just enjoy your experience.
The device even includes a built-in ammeter, so you know how much electricity your solar panels are producing. This is the only charger on our list that has this very helpful feature!
The solar charger measures 11” x 16” x 1” when closed, and weighs just 21 ounces. Basically, it’s smaller and lighter than a laptop, so it’s easy to throw in a backpack when you’re on a day hike or moving around the city all day. Once unfolded, you’ll find four small solar panels wrapped in heavy-duty, waterproof canvas.
This is one of the more popular solar chargers for iPhones and other smartphones, and for good reason. Users routinely say the charger is durable, fast-charging, and well-priced.
Some seemed disappointed that the charger doesn’t provide a full 28 watts, but unless you’re in absolutely perfect conditions, no solar panel is going to provide its nameplate wattage – that’s just how it works.
Bottom Line: BigBlue’s solar charger is the perfect option to charge your iPhone. It’s extremely portable, low cost, and well-made.Learn More & Buy Now at Amazon
The most expensive item on this list, but also one of the most capable, Voltaic System’s Arc 20 is specifically designed to charge laptops and includes not only a solar panel, but a battery pack as well. It’s designed and built for those times when the utility grid is simply not an option.
Solar battery chargers designed for smartphones typically provide only 5 volts of power, as this is what smartphones, tablets, and other small gadgets need. The Arc 20 though includes three different power output options:
- 1 USB 5v/2A output
- 1 USB-C 5v/3A output
- 1 high-voltage laptop port (12V/6A, 16v/5A, 19v/4.5A, and 24v/3.5A)
The battery pack has a capacity of 24,000 milliamp-hours, enough for 1 laptop charge, 7 smartphone charges, or 3 tablet charges. The kit pretty much has everything you need to get all your devices running off solar, including:
- DC output for laptops
- 10 connectors for different laptops, but check the list to make sure your laptop is one of them!
- Car charger
- AC wall adapter
With pass-through charging, you’re also able to both charge the battery and your device from the solar panel at the same time. Voltaic Systems estimates 6 hours for a full laptop charge and 1 hour for smartphones.
The foldable 20 watt solar panel is wrapped in heavy-duty canvas and outputs 18 volts to charge the battery pack in just six hours – pretty quick considering the size of the battery pack.
The whole kit weighs just 3.25 pounds and is about the same size as a laptop, so you can add it to your backpack without too much trouble.
Customers absolutely love this kit. Its high cost relegates it to special use cases, so there aren’t as many reviews as for other cheaper items, but customers certainly put this thing through the ringer, claiming it’s for serious off-grid use and that it’s up to the task.
Peace Corps trips in West Africa and extended trips in the backcountry are just a couple of the situations people use this charger for.
Bottom Line: The Voltaic Solar Charger may be pricier than others on our list, but is built to take any extended, harsh off-grid trip you can throw at it. Buy it and know you’ll always have juice for your laptop, no matter what.Learn More & Buy Now at Amazon
When backpacking, you’re carrying everything right on your back for days at a time. Shaving weight from your pack means you can travel faster, longer, and with less fear of tiring out or injury.
With smartphones increasingly used as camera, compass, GPS, map, guidebook, notebook and emergency communicator, keeping your phone charged becomes increasingly important.
Of course, a solar charger is just one more thing to bring, but thankfully Renogy’s E.FLEX solar charger is perfectly designed for backpacking trips. First off, it’s just 0.08” thick and 10” x 6” in diameter, so it’s easy to fold flat in your pack or clip to the outside of your backpack while hiking.
Second, it’s incredibly lightweight at just 11.2 ounces – one of the lightest solar chargers, if not the lightest, on the market.
It comes with 4 suction cups and 2 small carabiners so you can attach it to the car windshield on the way to the trailhead or to your backpack or tent while in the backcountry.
At 10 watts, this solar charger doesn’t produce too much energy, but its certainly enough for your smartphone. Users note it can charge smartphones and laptops in a few hours, but it needs full sunlight to really charge efficiently. If you’re stuck in cloudy or rainy weather, 10 watts just isn’t enough to charge.
However, don’t let that turn you off to this awesome little solar charger. Renogy makes excellent solar-related products and their gear always enjoys top-notch reviews from customers. This small solar charger is no different. Most customers praise its charging abilities, simplicity, and light weight.
Renogy actually makes a few different models of the E.FLEX solar chargers:
- 10W Plus: This is the product we review here. It features a polycrystalline silicon solar panel and it’s thinner and lighter than the standard option below
- 10W Mono: About half the price of the 10W Plus, the 10W Mono is about 2 ounces heavier and almost 2x as thick (which, at 0.13 inches is still incredibly thin). Other than that, it’s got the same specs as the Plus (namely 5v/2A power output) at a much lower price.
- 5W Plus: All of the benefits of the 10W Plus, but half the wattage and only 5.6 ounces
- 5W Mono: Same as the 10W Mono, but only 5 watts and 6.7 ounces
Bottom Line: Renogy’s E.FLEX line of ultra thin solar chargers are the best option available for backpackers. They’re cheap, reliable, and extremely light weight.Learn More & Buy Now at Amazon
Energizer’s PowerKeep kit has a fantastic design that allows you to charge four AA or AAA batteries, but also use these batteries as a battery bank to charge your smartphone. Now that’s a great design! You can use them in your headlamp or top off your iPhone.
It comes with four NiMH batteries, the battery charger with integrated LED light, an adapter to charge AAA batteries, and a 6 watt folding solar panel.
The charger includes a single USB output so you can charge speakers, phones, or cameras. With the four AA batteries collectively totaling 9,200 mAh of capacity, you can charge your smartphone a couple times before you need to pull out the solar panel.
Users report that the included 6 watt solar panel can charge four AAs in about six hours in full sun. You’re also able to charge the batteries via an outlet or USB at home, so you don’t have to have a sunny picnic every time you need some fresh AAs.
With Energizer such a well-known company, you know you’re getting a quality product. User reviews corroborate this, with all noting the quality is great and the whole kit works as it should.
The only real downside to the kit is the high price, but considering you get a multi-use solar panel, AAs, and powerbank, it’s really not a terrible deal for something so flexible.
Bottom Line: The Energizer PowerKeep is probably the most innovative product on our list. Charge up the included AA batteries with the solar panel, take them out of the charger and use them in your gadgets, or keep them in the charger, plug in your phone, and use them as a backup battery bank. Now that’s cool!Learn More & Buy Now at Amazon
Tips for Choosing the Right Solar Charger
Solar battery chargers are pretty simple pieces of equipment. They’re just solar panels with some cords attached. Still though, there’s a few things you need to know if you’re in the market. Here’s a couple tips to help you find the right solar charger for you.
With solar chargers coming in sizes from 2 watts up to 30 watts, finding the right size for your needs is key. You want it to be big enough to keep your battery topped up, but not too big to the point where you’re just wasting money.
Most solar chargers for vehicle batteries come in around 5 to 15 watts. Larger vehicles typically require larger batteries, but it really depends on your vehicle’s phantom loads (ie power pulled from the battery even when the key isn’t in the ignition) and driving frequency. If you’re worried, 10 to 15 watts should be enough to keep any vehicle ready for use.
If you’re looking to charge your smartphone or tablet, you’ll probably want a larger solar panel. Most solar chargers for small devices sit around 15 to 30 watts, with the average around 22 to 28 watts. Exactly how many watts you need depends on the specific devices you want to charge, as well as how many devices. We recommend 20 watts or more for general use.
If you’re looking for a solar charger for your 12 volt battery (in other words, for your car, boat, or RV), you’ll want your charger to include, at least, a blocking diode (see above), and the correct cords for your application (alligator clips for short term use, battery terminal rings for long-term storage, cigarette adaptors if you want to charge in the car, etc.)
On top of that, you’ll want to ensure the panel can be installed in the manner you’d like. Does it have mounting holes in each corner? Can it be glued down or not? These questions are easily answered by reading the description and customer reviews, or even asking a question to the extremely-helpful Amazon community.
If you want to charge your 5 volt gadgets (smartphones and tablets), you’ll need to ensure the charger has enough ports for your needs (usually 1 or 2 USB ports) as well as the right type – USB, USB-C, etc.
Also, how about mounting? Does it have holes in each corner? Does it come with carabiners or suction cups to clip or stick to different surfaces? Take a second to read the description and reviews to see exactly what features come with the charger.
Solar battery chargers really aren’t expensive at all, typically falling between $20 and $60, depending on the size of the solar panel and the features included. The higher end models can come in at $100+ and tacking on a battery pack can add even more.
If you’re looking at solar chargers for your vehicles or boat, you’ll find that solar chargers are a bit more expensive than a typical battery charger that you plug into your wall. However, the benefits of a solar charger, their portability and versatility, far outweigh the slight cost increase.
Charge Controllers and Diodes
If you’re looking at solar chargers for cars or boats (or any other 12 volt application), you’ll probably see a lot of discussion around blocking diodes and charge controllers and whether this or that particular product needs one. But what the heck are they? And are they even important?
Blocking Diodes – You Need Em!
Most of the better solar chargers include a blocking diode integrated into the solar panel. The diode allows electricity to flow towards the battery, but blocks electricity following in the opposite direction. Without a blocking diode, your battery can actually send electricity back to the solar panel at night, when the panel isn’t producing electricity.
If your solar charger doesn’t have a blocking diode, you’ll need to disconnect the charger from your battery each night. With a blocking diode, you don’t have to worry about this unnecessary waste.
Unless the manufacturer specifically notes that blocking diodes aren’t necessary (like DuraVolt above), make sure your solar battery charger includes one!
Charge Controller – You Might Need It
Charge controllers keep your solar panel from overcharging and damaging your battery. For large solar installations, they’re a required piece of equipment. Small battery chargers though usually don’t include a solar charger and many manufactures note that small 12 volt solar panels really don’t need a controller, as they don’t provide enough juice to overcharge the battery.
Others however recommend purchasing and using a charge controller for any solar panel larger than 5 watts. Many people report they use their solar battery charger without any charge controller and haven’t experienced any negative issues.
However, if there’s ever any voltage spikes or your battery charger is left connected to your battery for an extended period of time, there’s a chance you could damage it.
If you’re worried at all, it’s probably best to either buy a solar charger with an integrated charge controller (like the Battery Tender above) or spend the extra $20 on a separate charge controller.
Pros and Cons of Solar Chargers
Solar chargers are a great way to keep your batteries easily charged up, but they’re not perfect. Let’s take a look at the pros and cons of solar chargers.
Pros of Solar Chargers
- Free energy: This is an easy one. Once you buy the solar charger, you never have to pay for electricity or generator gas to top your batteries up. Use it for a year or 20 years, your fuel costs will be the same: absolutely zero.
- Charge without utility power: This is the biggest draw to solar chargers. Since they’re powered by the sun, you’re able to charge your devices anywhere there’s sunlight. On your boat, while camping, in your RV, your driveway – you name it! No longer do you have to worry about moving your batteries into the garage or running cords outside. Just hook the charger to your battery and put the solar panel in the sun!
- Easy setup: No need to take out your batteries or move your boat or ATV close to the garage. Just hook your battery or smartphone up to your solar charger and place the charger in the sun. Done!
Cons of Solar Chargers
- Not a ton of power: Solar chargers typically only produce about 2 to 30 watts of electricity, depending on intended use. It’s more than enough to keep your battery topped up, but that’s really not a lot of electricity at all. You’ll need to base the size of your charger on your own needs. The more you use the battery, the bigger your solar charger needs to be. If you want to keep two batteries fully charged, you’ll need to buy two solar chargers.
- Higher cost: Solar battery chargers are more expensive to purchase than plug-in chargers. That’s just a fact. Of course, with a solar charger you don’t have to pay for any electricity, but we add this to the list of cons to keep everything balanced.
Overall, we think the flexibility, functionality, and ease of use of solar-powered battery chargers easily make up for their higher purchase price.
If you’re looking to keep your vehicles’ battery or smartphone topped up, solar chargers can get it done.
We hope you enjoyed our list of the best solar battery chargers in 2021. Just as a quick review, we looked at dozens of battery chargers on the market, and chose the best in 8 different categories. Here are the top picks.
Compare the Best Solar Battery Chargers for 2021
- Best Solar Battery Charger for Cars: Battery Tender Solar Charger
- Best Solar Battery Charger for Boats: DuraVolt 20W Marine Solar Battery Charger
- Best Solar Battery Charger for RVs: DuraVolt Magnetic Battery Maintainer
- Best Solar Battery Charger for Motorcycles: POWOXI Solar Battery Charger
- Best Solar Battery Charger for Phones: BigBlue 28W Solar Charger
- Best Solar Battery Charger for Laptops: Voltaic Systems Arc 20 Rapid Solar Laptop Charger
- Best Solar Battery Charger for Backpacking: Renogy E.FLEX 10W Ultra Thin Solar Charger
- Best Solar Battery Charger for Rechargeable Batteries: Energizer PowerKeep
Take a look at the products above and find the best solar battery charger that’s right for you! Like we’ve pointed out, the best options are durable, cost-competitive, and backed up by excellent customer service. And beyond the versatility and ease of use, using a solar battery charger and running your life off the sun –even if it’s just a tiny part of it – is great for you and the environment!
Image Credit: CC license via Flickr