A solar power bank is essential for outdoor enthusiasts, providing potentially endless energy. It’s ideal for charging smartphones, cameras, and other gadgets when we don’t have access to energy sources. It can also be handy in the event of a blackout.

These handy portable devices have evolved in several styles, but cell phone sizes are the most common. They typically feature a single solar panel or several collapsible panels.

Solar chargers with panels are more compact but slower to recharge using the sun’s energy. More panels can speed things up a bit, but they’re bulkier.

The fastest way to recharge both is to plug a USB into a traditional power source and store the energy. Once the power bank has been filled, it can charge external devices and possibly be recharged by solar energy.

How a solar power bank works

I will show you the working principles of solar power banks. You should know that the recharging process involving these small devices is the same as for larger solar panels, i.e., photovoltaics.

It is a rather complex electrochemical process in which those tiny particles of light known as photons transfer their energy to the electrons in the silicon, the semiconductor of which the panel cells are made. The electrons are as they were set in motion, and this activity produces electricity which is transferred to a lithium-ion battery.

One of the most exciting features of solar power banks lies in the possibility of accumulating energy, storing it inside the batteries, and then using it when necessary. Therefore, it is unnecessary always to have sunlight available, as is the case with simple solar chargers. To recharge it, position it so that the panels receive direct sunlight: the operation takes place automatically and in a highly natural way, without the need to activate anything.

Next, I will show you the various characteristics of these devices to give you a complete picture as regards the capacity to store energy, the different types of panels, the connectivity, and how you can recharge smartphones, tablets, and laptops.

Finally, I will provide information regarding the dimensions and weight of the models in circulation and other properties, such as resistance. They are all distinctive elements worth considering to choose the ideal one for your needs among the best solar power banks.

Panel typology of the Solar Powe Bank

There are two types of panels: monocrystalline and polycrystalline. Monocrystalline panels have a darker color, a feature that allows them to attract more sunlight. They are also suitable for use on not mainly sunny days thanks to their particular orientation, although, with unfavorable conditions, they can generate less energy.

Polycrystalline (or multi-crystalline) panels instead have a blue color and are usually cheaper than monocrystalline. They are less efficient than the latter, requiring a more significant extension to generate the same energy. However, they make better use of the sunlight throughout the day and can optimize the management of temperatures better.

The capacity of the Solar Powe Bank

I mean the battery’s capacity integrated into the solar power bank, measured in mAh (milliampere-hours). You will find this value indicated in the specifications of the products you will view, and you will need to adjust according to your needs.

You will have to consider that a 5,000 mAh battery is sufficient for a single recharge of a smartphone, after which it will be necessary to put the solar power bank back in charge to be able to use it again.

If you need to recharge a tablet or more than one smartphone simultaneously, I suggest you evaluate the purchase of a solar power bank between 8,000 and 12,000 mAh. At the same time, it is advisable to go above 25,000 mAh for a laptop.

Another aspect to consider is the actual performance of the battery, which often does not correspond to that nominally indicated in the product specifications. It is good to remember that you may experience a natural energy dispersion of about 20-30%. Hence, the advice is to choose a slightly higher capacity than needed. Finally, consider the charging time when choosing, which is much slower than when connected to the mains.

Doors of the Solar Powe Bank

Other important data to evaluate are the number and type of ports on the solar power bank and their delivery intensity. If you frequently need to charge multiple devices, even simultaneously, checking that it has enough ports makes sense.

The latter can be of various types: the USB A is the standard one that allows insertion only in one direction. On the other hand, USB- C represents the latest generation connection characterized by a slimmer design and higher potential, therefore suitable for connecting more recent devices.

The Micro-USB ports are instead generally used to recharge the solar power bank itself, a handy alternative when it is not possible to take advantage of the solar panels. The Lightning ports are instead dedicated to Apple’s home connectors for iPhone, iPod, and some iPad models.

Ports can also have different power delivery strengths, which could radically affect the charging speed of devices. This value is expressed in amperes (A). It is often divided among the ports (so if you charge multiple devices simultaneously with the same power bank, the maximum power supplied will be divided among the various ports, and you cannot take advantage of all the power on all doors simultaneously).

Most of the ports have an amperage of 1A or 2A. Still, with the rapid evolution of the technology that characterizes these devices, it is increasingly easy to come across a higher value.

However, check that the device to be recharged also supports these intensities: if your smartphone, for example, reaches a maximum amperage of 1A, even connecting it to a 2A solar power bank will not impact the recharge times.

You may also find another value expressed in volts indicated: in fact, these are two units of measurement, volts and amperes, both relating to current but which, in reality, refer to different electrical quantities.

Volt identifies more precisely the voltage that the power bank’s output port can handle, which, as a rule, is equivalent to 5V. A surefire way to determine solar power bank compatibility is to compare it to the charger specifications of your smartphone, tablet, laptop, or whatever device you want to charge.

Charging mode of the Solar Powe Bank

Solar power banks can offer two main charging methods: standard and wireless. The first is the more traditional and widespread one, which is performed using special cables to be connected to the respective output ports of the solar power bank and input of the device to be recharged.

The wireless mode, on the other hand, is establishing itself more recently with the appearance on the market of different types of devices capable of supporting the technology and provides for the possibility of activating recharging through electromagnetic induction simply by placing the device on the appropriate coils transmission that the solar power bank is equipped with.

Furthermore, in recent times, a new technology called smart devices has also been gaining ground, which allows you to detect the devices connected to the solar power bank and automatically adjust the necessary charging speed.

Another technology that some solar power banks are equipped with is Quick Charge (fast charging), but it is good to check that the devices to be recharged are also equipped with it. It is only present in specific Snapdragon chips from Qualcomm mounted in some devices such as computers and smartphones. These allow for more effective management of electricity via the USB interface and make recharging much faster possible.

Dimensions and weight of the Solar Powe Bank

I warmly advise you to check the dimensions and weight of the solar power banks so as not to end up with an uncomfortable, bulky, and difficult-to-transport product. There are, for example, several models designed for outdoor excursions and camping equipped with multiple panels for intensive use and to ensure greater energy availability through huge batteries, which involve a considerable load.

Often these models are foldable and extend to cover a large surface. Therefore, carefully evaluate the daily use you will have to make of the solar power bank. If you need a certain versatility, they could be the right solution. In contrast, if you only need it sporadically to recharge your smartphone, you’d probably be better off focusing on smaller models.

Resistance of the Solar Powe Bank

You’re rightly wondering what happens, for example, if you leave your solar power bank charging on your windowsill and an unexpected summer storm arrives, particularly heavy with rain. Your doubt is legitimate, so I suggest you check the resistance characteristics before purchasing. The good news, however, is that most models are equipped with excellent materials that can withstand harsh environmental conditions, starting with water.

Therefore, ensure that good waterproofing is indicated in the specifications as a property. Some models are wrapped in a layer of rubber, capable of protecting against shocks: it could be helpful if you have to take them with you on long excursions or for trekking, perhaps hooking them to your backpack using the carabiner they are equipped with to capture as much energy as possible sunny as possible.

In these situations, they must also be protected from dust and sand, which occurs through special coatings such as ABS material and silicone, which are heat resistant and recyclable, capable of preventing external elements from penetrating the internal circuits and causing irreparable damage.