iSIS Freeloader Solar Charger Review – Designed for the Hike

I’m very pleased to have had the opportunity to do an in-depth review of the iSIS Freeloader. A solar phone charger, which in my opinion is pretty damn close to being the perfect portable battery pack to take on an outdoor adventure.

The iSIS freeloader solar phone charger reviewIn the Box

  • The iSIS Freeloader Solar Phone Charger
  • An impact and water resistant matte black rubberised case
  • A velcro strap to easily attach the charger to a backpack
  • An additional mirco USB charging cable
  • An in depth user manual

About the iSIS Freeloader

The iSIS Freeloader is a Solar Battery Pack manufactured by Solar Technology International Ltd, a UK company based in Gloucester. Unlike the vast majority of portable phone chargers, the iSIS Freeloader feels “British Made”.  The device somehow manages to appear extremely robust and is yet surprising light when compared to other portable chargers.

The iSIS Freeloader Solar Battery Pack with intergrated charging armsThe front of the iSIS is largely occupied by the highly efficient 220mA solar panel surrounded by a matte black trim. There is a small LED display at the bottom which indicates the current charge source (solar or USB) and 4 bars to indicate battery storage.

The main body of the device appears to be cast from Aluminium with a brushed satin finish which looks to have been coated in a lacquer to prevent any tarnishing when exposed to the elements.  The aluminium body, which is visible on the sides of the charger, houses 2 integrated charging arms.  The right arm has a lightning connector suitable for most Apple products made after 2012 and the left arm has a standard Micro USB connector which is suitable for pretty much all other portable devices.

The iSIS Freeloader Solar Phone Charger has a built in support stand to help position the device when solar charging
On the rear of the iSIS solar charger is a support stand which is neatly recessed in to the body.  The angle of the stand can be easily adjusted to maximise sunlight exposure on the solar panels.
The iSIS solar charger used with it's case and backpack strapThe integrated charging arms and the built in stand were definitely 2 of the main reasons that the Freeloader first appealed to me over other solar phone chargers.

After testing this product on a hike, however, I have to say that both these features are far less practical than just using the case and the Velcro backpack strap.

The water-resistant rubberised gel case and the Velcro strap that come with the iSIS Freeloader make this solar charger a perfect addition to your hiking kit.  Once you have attached the iSIS to the strap on your backpack you are instantly able to get the solar charger in it’s optimal position, simply by the placement of your bag.

As you can see from the picture below, by leaving the iSIS on the strap of my hiking bag, I am able to easily position the solar panels to maximise their effectiveness while keeping it off the ground and inside it’s water and shock resistant case.

The iSIS freeloading solar charging while positioned on the strap on my hiking bag

During my hike, I found that I could easily orientate the device towards the sun, even if I wasn’t walking directly towards it.  On my return journey, when the sun was behind me, I was able to effortlessly reposition the solar panels by sliding the iSIS up the bag strap and over my shoulder.

Hiking with the iSIS solar phone charger mounted on my bag strapThe integrated charging arms are undoubtedly a nice feature,  but for me, the better charging option was to use the USB port and an external cable. This way I could keep the solar charger on the strap of my bag, and have it charge the phone in my pocket.

Technical Specifications

  • 4000mAh Lithium polymer battery
  • 200 mAh Solar cell
  • Lightning & Micro USB integrated cables
  • Charges 2 devices simultaneously
  • Dust and weather resistant port covers
  • Impact resistant from a 1m fall
  • Water resistant (in it’s case)

The high density portable solar panels on the iSIS freeloader are said to be 50% more efficient than it’s competitors which allows it to be far smaller than it’s rivals while still matching the charge speeds.  The internal Li-polymer battery has a respectable 4000mAh of storage capacity making it capable of recharging most smartphones 3 times over as well as GPS devices.

There are other portable phone chargers with far more capacity that the iSIS, but additional storage comes at a cost of size and weight, which are both important factors when choosing your hiking gear.  For this reason I believe the iSIS Freeloader has struck the perfect balance between it’s capacity and it’s physical size making it ideal for lightweight day hikes.

Making the most out of a Solar Phone Charger

Charging a Moto G using the iSIS Freeloader solar phone chargerSolar Charging the iSIS Freeloader through the windowRather than stowing the iSIS Freeloader away and only using it when you are hiking, you can actually make good use of the device at home. I placed it on my window ledge and it began taking a charge through the window.  I imagine that it won’t be quite as effective as charging it in direct sunlight, even so it’s free power which has to be a good thing right?

I also like to hook a USB fan up to a portable phone charger on a hot day and use it as a cooling fan while I’m at my desk.Use a portable phone charger with a USB fan to keep you cool on a hot dayPrice and Availability

The iSIS Freeloader portable solar charger is priced at £64.99.  Initially I thought this was a little expensive for a solar phone charger,  but after getting my hands on the product and testing it on a hike,  I can confidently say it’s worth every penny.

Available to buy online at  or find it at your nearest electrical or outdoor goods store using Freeloader’s “where to buy” page.

– 11/12/14
The current best price available on the iSIS Freeloader is £52.65 from


  1. Hi in June this year I will be walking the Camino de Santiago for the homeless charity Emmaus. I was hoping that someone may be able to help me in the way of sponsoring me with a solar powered phone charger that can charge my phone whilst I am walking. You can find my details on my fundraising page-

    Once you have looked at my page you may understand why I am asking for your help. As last year this was my main problem as I ended up in hospital, I was lucky that 3 other pilgrims found me and phoned me an ambulance as I had concussion and hypothermia. My phone was out of battery and I was unable to call for help myself.
    The isis is a perfect device and essential as I am walking on £95 a fortnight as I suffer from anxiety and depression since losing my husband in 2012, I also have dyspaxia.
    I really hope and pray someone will read this and help me by sponsoring me with one of these devices as I will be sleeping homeless (real pilgrim style along the way).
    My money will go on food along the way.
    I hope to hear from someone soon as the great British public are very kind people, I’m sure someone will understand my predicament and be able to help me. Also I could do with any advice if you can think of another way of me being sponsored in the way of an Isis as this is ideal for my needs and essential for my trip.
    Please can you share my page with your friends and family to raise as much awareness of my Camino and fundraising.
    God bless, peace and love

    • Hi Andrea,

      Unfortunately I don’t actually stock or sell the ISIS, I just reviewed it. I can imagine that a Solar powered phone charger would be a pretty essential piece of kit for your walk. The ISIS freeloader is a really good choice for hiking, although there are other less expensive options that work equally as well. Take a look at the Poweradd Solar Charger it’s a 1/3rd of the price and has more storage capacity (7200mAH’s).

      Good luck with your fund-raising.

  2. I’ve had an iSIS freeloader for almost a year now, I always take it on hikes even when the chances of sun are low, I still get a couple of full chargers just off the battery pack storage, which is more than I need on most occasions.

  3. Thanks Terry,

    The fan idea might actually work, certainly worth taking one on a summer hike, even if it’s just to circulate some air in your tent.

    Great tip on using a portable battery pack to charge a console controller too!

    Thanks for taking the time to comment 🙂

  4. Nice review, I have an Anker Solar Charger which works well, but it’s fairly large and doesn’t have a battery pack. I like the idea of being able to have a small compact solar charger that can store as well as charge.

    Good tip about the fan too!, I’m wondering if I can have the iSIS on my bag strap with the fan blowing on my face, might look a tad silly though….

    Oh, here’s another tip for making use of a portable battery pack- You can charge your games console controllers with one. That way is the controller dies and you want to carry on gaming, you don’t have to sit 3 feet from the screen with the USB cable plugged in to the PS3.


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