This is the first portable solar panel charger I bought. To be honest, not sure yet where I am going to use, most likely, during a camping (pretending I don't have battery bank...). Anyway, here is my review:Like:1. the folded size is very good. Less than a letter paper so easily put in a backpack;2. It looks durable. The panel is flexible. My past experience is crystal type, which is rigid and fragile. The canvas should last lone.Dislike:1. No manual, no cable. The USB-A port look shabby.I test it with my USB power bank and I can confirm it does work. Can't comment on charge speed but I think 35W-ish should be similar to a regular battery charger. So if you a frequent camper, I assume it would be helpful. I definitely would put a USB-A to multiport cable inside. If I frequently use it, I would also put a small battery bank in the pocket to store the energy. Overall, this is a budget solar panel charger. I googled and it suggests that they can last very long. So for a toy or gadget, I am willing to buy one.

Honestamente la calidad del producto es bastante de “juguete” por ese precio se consiguen mejores artículos aquí en Amazon

First Impressions of JOYIDEAVA Portable Solar Panel 35W Mobile Phone Solar Charger with Dual USB Outputs Waterproof Smartphones Battery Charger Foldable Solar Charging Panel for Camping, Hiking and Outdoor Trip (Black)⭐⭐⭐⭐⭐ 5-stars✅ Generates usable energy✅ Portable Folding Design✅ (2) USB-A output ports - I observed 5, 9, and 12 volt outputs✅ Charging (or ON) indicator✅ Small storage pouch✅ Includes (4) small carabiners✅ Feels solidly built, adequately rugged✅ Easy to use, plug and aim at sun✅ Competitive pricing❌ Slightly heavy for long distance carry❌ No USB-C output❌ I would have liked mounting eyelets on both sides❌ I would have like an output volt/amp meter❌ Car output would have been nice (trickle charge car 12v battery)This is the real deal! I really like this product because it works – however to be satisfied or have a satisfying experience, a basic understanding of solar panels, electricity, and electronics should be understood.The max rating for a portable solar panel can misconstrue the typical output. For the solar panel to achieve the max output, all factors must be ideal which is nearly impossible to achieve especially if the panel isn’t used in a perfect location such as the desert in the summer time with the sun at its highest arc.So, if we can’t expect the max output, what can we expect? At the time of this review and my testing, the sun was slightly past the spring equinox. This means that the sun wasn’t at its brightest nor lowest arc.What was interesting about what I observed during my test was that the output exceed the printed specifications for the panel. I expected only nominal USB 5 volt output but observed 9 and 12 volt outputs for a maximum peak output of 20ish watts. However a typical sustained output of 10-11 watts seemed to be the average output.With that said, on a good sunny day, a 10000mah power bank could charge somewhere between 3-5 hours (this also depends on the charging capabilities of the power bank) and possibly charge a smartphone from empty in around 2-4 hours depending on the smartphone and battery inside.On a cloudy day, I only achieved 1-2 watts and sometimes no charge – which made this product fairly useless outside of a castaway shipwrecked scenario.For this product to be most effective, the panel needs to be angled perfectly perpendicular to the sun’s rays. Even the slightest off angle drastically decreases power output.Most USB rechargeable products have a battery capacity or watt-hour rating printed or listed in the specifications. To get an estimate, divide the Watt-hour (Wh) by 10 watts output, to get an idea of how many hours it will take to recharge. In case you want to check the math: Volts x Amps = Watts. Typical batteries are nominally 3.7 volts x Amp/hours = Watt/hours. Since there are inefficiencies in charging batteries (losses to heat, mostly), the typical efficiency is 65-80%. So for example, a 20000mah power bank or device: 3.7 V x 20 A/h = 74 Wh. 74Wh / 80% (inefficiency) = 92.5 Wh estimated to recharge full from empty.I wanted to test this panel in non-ideal suboptimal conditions. I placed the panel to charge a 20k mah power bank out at dawn. I only changed the panel position once during the day. It was a partly sunny/partly cloudy day in late April (spring sun). The power bank charged up 1/3rd which I thought great. This is enough power to charge up even the largest of smartphones full from empty.Obviously, this inexpensive solar panel isn’t a monster for recharging but it’s compact possibly provides sufficient power for light or emergency use scenarios. Despite some of its small shortcomings, I think the bang for buck ratio is still pretty high. 5 stars.If over long term use, my feelings change about this product, I will update this review. Thanks for reading and hope this helps.

I have been testing/using this JOYIDEAVA Portable Solar Panel to charge a 20,000mAh fast charging power bank. The conditions I'm using are less than ideal in that I'm charging by placing the solar panel on the front dashboard of my car while I'm at work. Glass reflects quite a bit of light which diminishes the amount of light getting to the panels and it still charges quite effectively. Over the course of 9 hours this charger will increase the battery pack by 10% or around 2,000mAh. In direct sunlight I am sure the results would be substantially improved.I wouldn't say this is practical for everyday charging but in the event of a lengthy power outage (severe weather, power grid failure, zombie attack) this solar panel charger would become invaluable in an emergency.I removed one star due the lack of a USB-C charging port.

This portable solar panel is perfect for camping and emergencies. It’s lightweight, folds up compactly, and still delivers solid charging power. I used it to charge my phone, a small power bank, and even a Bluetooth speaker while camping, and it worked like a charm. The dual USB outputs are great for charging multiple devices at once. It feels well made and sturdy, with a nice rugged look. Definitely a must-have if you want a reliable, eco-friendly power source on your adventures!

I didn't have hiking planned to test this, so I plugged in my S23 Ultra and put the solar panel in the sun and my phone in the shade. It charges pretty fast as well, about 10% every 10 minutes or so, so it definitely works! It is a bit heavy, but if you already have a backpack and need to charge your devices away from civilization or during a power outage, this will do the job. It was built well and felt sturdy enough to handle the jostling that would happen when hiking.