Over the past month, I’ve been testing 5 of the best solar power banks.
I tested their solar charging ability by measuring how much solar energy they collected, checked their battery capacity to spot any exaggerated claims, and used them to charge my devices day to day.
After all that, here are my reviews and recommendations.
(Spoiler alert: I was unimpressed.)
Quick Picks: Best Solar Power Banks
Here’s the TLDR version of my rankings if you’re in a hurry. However, before deciding to buy, I’d encourage you to first read the section on the problems with solar power banks.
- Top Pick: QiSa Solar Power Bank
- Survival Frog QuadraPro Solar Power Bank
- Blavor Solar Power Bank
- Anker PowerCore Solar 10000
- 4Patriots Patriot Power Cell
Check out the video version of the review below and consider subscribing to my YouTube channel for more videos and reviews of solar products.
Top Pick: QiSa Solar Power Bank
|Number of Solar Panels:||4||Solar Charging Test Results:||6.91 Wh (2nd place)|
|Tested Battery Capacity:||44.04 Wh (1st place)||Number of Charging Ports:||3|
|Wireless Charging:||Yes||Connector Type:||USB-C|
Pros: Placed first in my battery capacity test, placed second in my solar charging test, has wireless charging, has USB-C
Cons: Tested battery capacity was much less than listed battery capacity, listed battery capacity is so high that you must get airline approval to carry it onboard a plane
The QiSa was the clear winner of my testing. It placed second in my solar charging test, collecting 6.91 watt hours over the course of 2 days. That’s enough to charge up an iPhone 15 Pro battery by around 54%.
It placed first in my battery capacity test, measuring a total capacity of 44.04 watt hours, which was by far the most. That’s enough to charge most phones around 2.5-3 times.
It’s also got the best combo of features of any of the power banks I tested. It has 4 solar panels rather than just 1. It has 2 charging ports plus wireless charging, meaning it can charge up to 3 devices at a time. It has a flashlight. And it has a USB-C connector type, rather than the cheaper Micro USB.
If you want a solar power bank, this is the only one I’ve used that I can even begin to recommend. It’ll work well for topping off your phone outdoors when hiking or as a backup charger in an emergency situation.
It’s important to point out that its tested capacity of 44.04 watt hours was wildly off its listed capacity of 143.56 watt hours — only 30.7% of its listed capacity. Sadly, some power bank brands on Amazon have gotten into an unfortunate habit of exaggerating their capacities. The funny thing is, at that listed capacity, the TSA says you have to get airline approval to carry it onboard.
So, despite being the winner of my testing, it gets the most lukewarm recommendation from me possible. It’s just hard to trust the long-term quality of cheap power bank brands – let alone one whose actual capacity is so far off from its listed capacity.
|Number of Solar Panels:||4||Solar Charging Test Results:||8.36 Wh (1st place)|
|Tested Battery Capacity:||14.83 Wh (5th place)||Number of Charging Ports:||3|
|Wireless Charging:||Yes||Connector Type:||Micro USB|
Pros: Placed first in my solar charging test, has wireless charging
Cons: Placed last in my battery capacity test, is expensive
The Survival Frog QuadraPro placed first in my solar charging test, collecting a total of 8.36 watt hours over the course of 2 days. That’s enough to charge an iPhone 15 Pro battery around 66%. Not bad!
However, this power banks placed last in my battery capacity test. I measured a capacity of just 14.83 watt hours, which is enough to charge most phones about 1 time. Not good!
Couple that mixed performance with the high price of this unit and I came away feeling that it just isn’t worth it. Yes, it did come in first in my solar charging test and these are solar power banks. But, because they solar charge slowly, I found myself mainly using them as regular power banks.
It does have wireless charging and a couple carabiners which make clipping it to a backpack easy. It also feels the most premium of the bunch. If you want the solar power bank that’s best at solar charging, this is it. But its low battery capacity is hard to overlook.
|Number of Solar Panels:||1||Solar Charging Test Results:||0.86 Wh (5th place)|
|Tested Battery Capacity:||28.65 Wh (2nd place)||Number of Charging Ports:||3|
|Wireless Charging:||Yes||Connector Type:||USB-C|
Pros: Placed second in my battery capacity test, is the cheapest option at the time of publishing, has wireless charging, has USB-C
Cons: Placed last in my solar charging test
The Blavor solar power bank is consistently one of the bestselling ones on Amazon, and copycats abound. So how do these popular 1-panel models measure up?
Not very well, I’m afraid. The Blavor placed last in my solar charging test, collecting a mere 0.86 watt hours over the course of 2 days. That’s not even 7% of an iPhone 15 Pro battery. Yikes.
However, it did have the second highest tested battery capacity, at 28.65 watt hours. That’s pretty good for a 10,000 mAh power bank.
The USB-C connector and wireless charging are nice touches that make it a decent option if you charge it from the wall and use it as a regular power bank. Just don’t expect to ever get much, if any, power from the solar panel.
|Number of Solar Panels:||1||Solar Charging Test Results:||1.58 Wh (3rd place)|
|Tested Battery Capacity:||27.45 Wh (3rd place)||Number of Charging Ports:||2|
|Wireless Charging:||No||Connector Type:||Micro USB|
Cons: Poor solar charging ability, mediocre battery capacity, no wireless charging, no USB-C
Anker is one of the most popular brands of power banks — and they’ve made a heavy push into solar generators this past year — so I was excited to try out their take on a solar power bank. I personally use their wall chargers at home and carry their standard power banks when hiking and camping, so I was admittedly a bit partial to this one going into testing.
The PowerCore Solar 10000 turned out to be mediocre. It placed third in both of my tests. It did collect the most solar energy of the 1-panel models, which I guess counts for something. But its 1.58 watt hours collected — around 12% of an iPhone 15 Pro battery — are nothing to write home about.
It has a Micro USB connector and no wireless charging, so you don’t even get any of the cool features that you can find in the competition. I’ve tested a handful of Anker products over the years and know that they’re quick to axe an underperforming model. My guess is this one won’t be available for much longer.
|Number of Solar Panels:||1||Solar Charging Test Results:||0.96 Wh (4th place)|
|Tested Battery Capacity:||21.22 Wh (4th place)||Number of Charging Ports:||2|
|Wireless Charging:||No||Connector Type:||Micro USB|
Cons: Placed second to last in my solar charging and battery capacity tests, no wireless charging, model tested does not have USB-C (though there is a newer model that has since come out that does have USB-C)
Note: Since I bought and started testing these solar power banks, 4Patriots has released an updated version of this model, called the 4Patriots Patriot Power Cell CX. At the time of publishing, the original model is still available on Amazon and appears to be the more popular version there based on Amazon’s publicly available sales data.
The Patriot Power Cell placed second to last in both my solar charging and battery capacity tests. After 2 days in the sun it collected just under 8% of an iPhone 15 Pro battery, or 0.96 watt hours.
Two days in the sun to charge a phone just 8% is yet another reminder of how bad the 1-panel models are. The solar panels are just too tiny to collect any meaningful amount of solar energy.
Its tested capacity was 21.22 watt hours, which is enough to charge a phone around 1.5-2 times. That’s the worst of the single-panel models.
The Patriot Power Cell charges using Micro USB (though the newer version has upgraded to USB-C), and it doesn’t have wireless charging. Its combo of poor performance and subpar features made this my least favorite of the bunch.
The Problems with Solar Power Banks
From the reaction to a viral video I made about solar power banks, I realized most people come in expecting them to generate a lot of energy. They think this thing is key to keeping all their devices powered up for free. What a find!
They buy before they do their research. It arrives, they put it outside to charge and bring it in a few hours later to find that — what’s this? — it didn’t charge at all! They write it off as a waste of money, a gimmick.
Let’s start by setting realistic expectations: solar power banks solar charge very slowly.
After leaving 5 outside for 2 days, the 1-panel models collected an average of 1.13 watt hours. An iPhone 15 Pro has a 12.7 Wh battery. That means, after 2 days, they collected enough energy to charge an iPhone 15 Pro battery by about 9%. Two days. Nine percent. Not good.
The 4-panel models fared much better, collecting an average of 7.64 watt hours, enough to charge an iPhone 15 Pro battery by around 60%. So, yes, solar power banks do work. But temper your expectations greatly.
Is that enough to help you charge your phone a bit while outdoors or in an emergency situation? Yes, especially with the 4-panel models.
Is it enough to replace any meaningful amount of your electricity usage with solar energy? No, certainly not.
Is that enough to let you solar charge your phone regularly, such as by putting the power bank in a window, clipping it to your backpack, or placing it on your car’s dashboard? Nope.
After months of using mine, I’ve come to the following conclusion: They are suited for a very specific set of use cases, particularly hiking, camping, and as an emergency backup charger. If that’s what you want to use one for, go right ahead, they’ll work okay for those situations. Use one for anything beyond that and you’re setting yourself up for disappointment.
Plus, solar power banks have a flaw that’s hiding in plain sight: the battery pack is connected to the solar panel.
And that’s partially the selling point — it’s an all-in-one battery and solar charger. However, what that means is you need to put the battery pack in direct sunlight in order for it to solar charge.
During testing, my solar power banks reached 140°F (60°C) on a mild day in October when it was 72°F (22°C) outside. But the lithium batteries inside these power banks do not like getting hot. Using them in a way they are designed to be used — as solar chargers — can damage the battery pack.
You’ve probably gotten a warning on your phone that it’s overheating from leaving it in direct sun for just 10 minutes. Solar power banks need to spend hours to days in direct sun in order to collect a meaningful amount of energy.
Hopefully we’ll soon see solar power banks with solid-state lithium batteries hit the market. It appears from the scientific literature that solid-state batteries may have much wider temperature ranges, among many other benefits. Fingers crossed that in a couple years’ time the overheating issue is a moot point. But that doesn’t solve the issue of slow solar charging.
A better alternative is probably just buying a dedicated solar charger and using that to charge a regular power bank. That way you can keep the battery out of direct sunlight. Not to mention, solar chargers tend to have bigger solar panels and thus output more power.
How to Choose the Best Solar Power Bank for Your Needs
Number of Solar Panels
The solar power banks I tested either have 1 or 4 solar panels.
One-panel models: Solar power banks with 1 panel solar charge incredibly slowly. If you leave one outside in the sun to charge for an entire sunny day, you can expect it to collect enough solar energy to charge your phone around 5-10%.
Four-panel models: The 4-panel models performed much better at solar charging. They have 4 times the solar panels but they collected roughly 7 times as much solar energy on average. If you want a solar power bank that can actually collect a meaningful amount of solar energy, these are the models I recommend. They are a bit pricier, but I think they’re worth it.
Because solar power banks solar charge slowly, it’s important to pick one with a good battery capacity. Typically, the higher the listed capacity, in milliamp hours (mAh) or watt hours (Wh), the greater the actual capacity.
However, beware of power banks exaggerating their capacity — an all-too-common occurrence. If a solar power bank has an extremely high listed capacity for an attractive price, it’s probably exaggerated.
To help you understand the power banks’ actual capacities, I charged them up overnight and then tested them with a dummy load and a power meter. Here are the results:
|Brand||Tested Capacity||Listed Capacity||Percentage|
|QiSa||44.04 Wh||143.56 Wh||30.7%|
|Survival Frog||14.83 Wh||24.05 Wh||61.7%|
|Blavor||28.65 Wh||37 Wh||77.4%|
|Anker||27.45 Wh||38 Wh||72.2%|
|4Patriots||21.22 Wh||29.6 Wh||71.7%|
Note: I have reported the power banks’ capacities in watt hours (Wh) rather than the more common unit of milliamp hours (mAh) because the voltage of the battery pack is different than the charging voltage. Watt hours take voltage into account while milliamp hours do not. For more on this, you can read up on how to calculate watt hours from milliamp hours. Also, for brands that only listed their capacities in mAh, I converted them to Wh using a voltage of 3.7V, the standard nominal voltage for Li-ion batteries.
Number of Charging Ports
Pick a solar power bank that can charge as many devices as you need. All the power banks I tested have at least 2 charging ports. Three of them — the QiSa, Survival Frog, and Blavor — also have wireless charging which means they can charge 3 devices at a time.
Most of the charging ports are still USB-A, but the Blavor also has a USB-C port with input/output.
The 2 connector types for wall charging the power banks were either Micro USB or USB-C.
Micro USB is an older and slower connector type, meaning it’ll take longer to charge a power bank from the wall.
USB-C is a newer connector type that allows for faster charging.