RAVPower 16W Solar Charger with Dual USB Port (Foldable, Portable) High Efficiency Outdoor Solar Panel for Smartphones Tablets and More

So I bought this solar panel just to see if it is any good for travel use paired with a RAVPower 16750mAh power bank. After giving it a fair testing period of 1 month, I was definitely impressed with the performance and sturdy build, it charged the previously mentioned power bank from 0% to 100% within 8 sun hours in mildly cloudy weather conditions. Few months down the road, I have noticed some goo probably glue around some of the sewing parts. After inspecting the rest of the panel it did not seem to have any more damage nor performance loss, so I wiped the substance off and carried on using it. The following day it stopped working, neither of the USB ports provided charge even though it was a sunny day. I have decided to contact the customer support, they have responded within 24 hours since my letter was sent which is very fast and offered me a replacement panel as that one could have been defected whilst in the production. I have received the replacement panel already, hopefully this one lasts me longer. Happy customer so far, I will try to update this review after a couple of months, if I do not forget. Portable Charger RAVPower 16750mAh Power Bank External Battery Pack with Most Powerful 4.5A Output and iSmart Technology - White

Bought this solar charger because I wanted to attempt to my make my phone run purely off solar energy for most of the year. Doing this by charging power banks in the day and leaving it stored for night time charges for my phone! So far so good, the charger charges pretty well in the sun and to a surprise it does really well in cloudy days too! Would recommend this Ravpower 16w Solar Charger to anyone wanting "free energy".

I bought this item for use while backpacking for occasions when I might not have access to an electricity supply. The first and last tests of this 16 watt unit were in southern Italy with clear skies. Whilst the device kicks out a 'credible' output,. opportunities to use it are obviously quite limited when sightseeing. Hang it on the back of your rucksack and risk getting mugged? A Naples street cafe owner couldn't understand why I selected a table in full sun, rather than in the shade. It was because I wanted to spread out the solar charger. I also overstayed my welcome while I waited for the phone charge to reach 95%, long after I'd finished my refreshments. I've now upgraded to the RavPower 24 watt model in the hope it will be even more effective. These are very solid and well made pieces of kit. When I contacted the seller, the customer service was phenomenal. The difference in bulk and weight between the 16 watt and 24 watt models, for carrying around, is minimal so I would strongly recommend the 24 watt model.Update: I took delivery of the 24w model and tried it out in the UK in August. First impressions with the charging power were favourable. I could believe it was producing at least 2 amps. But when I went to Greece in September, the sun was brighter and the charging power went down! It wasn't especially hot in Greece in September - about 30C. Customer service made some suggestions but I don't think I was breaking any of the guidelines. So I've ended up disappointed and will probably try a different brand of solar charger next. The RAVpower devices seem to need to stay unusually cool in order to work properly.

The device actually REVERSES charge flow sometimes; it begins to drain the battery of connected devices. I assume this is a fault of the "smart charging" technology. I had the previous version (with only 2 PV panels) that version was "dumb" and worked fine. I tried charging a 2 different battery packs and 4 different phone/tablets and observed this even when phones were switched off. I measured this phenomenon with a multimeter (voltage across connections as well as current and while at it, resistance) I measured at different light conditions (although not in a lab with controlled lux / lumens-distance parameters). The phenomenon was very subtle;1. flow of charge is initiated2. flow of charge stalls (probably the smart technology attempting to second guess the battery state of the connected phone/device from some initial voltage change/drop3. flow of charge reverses and after some time device battery level (before versus after) can be measured as lower than would be the case at normal rest/non-use.Make of that what you will.Ciaran

The first item I received was defective. One of the USB cables was loose, where it attached to the solar panel and charge would cut on and off as I jiggled it. Both USB ports were also making strange crackling noises. I was sent a replacement, and initially it did charge correctly, but I would still occassionaly get a strange crackling noise from the USB ports. After about 10 days of use this developed into a full blown fault on both USB ports, where both were making clear electrical crackling noises. When attached to power banks the lights on the power banks flickered erratically in tandem with the eletrical crackling of the USB ports, and would not charge.It's a shame, as these are otherwise good panels. I used both panels I received according to the advice given. They will charge from both USB ports in cloud cover, and even occasionally light rain, from behind a window. But, they seem to have quality control issues.To receive 2 panels with the same general electrical fault is very bad.