Pros / The SunJack solar charger has dual charging capabilities: it can charge and be charged from two different sources at the same time.
Cons / It’s bulkier than most products we tested.
Verdict / Though it’s better at solar charging than any single-paneled power banks, the SunJack’s extra bulk makes it less desirable than top-performing products.
In our tests on solar phone chargers, all the products with four solar panels out-performed the products with fewer panels. The SunJack soaked up plenty of solar energy during both our sunny and cloudy day tests, and it has all the same features we love in our top picks. Oddly, however, the power bank is bigger than other products with the same specs and similar designs, making it a slightly less convenient product to carry around.
We set all the solar phone charges outside on both sunny and cloudy days. After four hours, we measured how far each battery could charge a Samsung Galaxy S5 from zero percent battery. The SunJack juiced the phone up to 59 percent on a sunny day and 48 percent on a cloudy day. That’s a just over 10 percent less than the X-Dragon solar power bank managed for each. Still, based on these tests, you could get a full smartphone charge out of the SunJack after a day in the sun.
Like the other products we evaluated, the SunJack charges much faster when charged via its microUSB input port than it does with the sun. With solar charging only, it may take a few days to completely fill the 10,000 mAh battery capacity. You could also use the solar capabilities for top ups, emergencies and to accelerate charging, as the SunJack can charge from both the solar panels and input port at the same time. Five tiny LEDs on the side of the battery let you know when it’s charging and its current battery status.
Several of the products we tested follow an identical form factor. The SunJack, X-Dragon and Hiluckey solar power banks all look like the same product with slight variations. The Hiluckey has fewer panels. The SunJack has larger battery dimensions and less texture on the back. The SunJack is water, dust and shock-proof thanks to its ABS coated body, leather-clad solar panels and port cover. You can attach it to a pack or bag using the little loop on one corner of the battery. It has two USB output ports and one microUSB input port. The back of the device houses a power button and an LED flashlight panel.
The SunJack solar charger is a good product. It’s four solar panels soak up plenty of sun and its water, dust and shock-proof design makes it great for outdoorsy activities like hiking and camping. However, it’s so similar to our top pick that if you’re looking for a four-paneled 10,000 mAh solar power bank, we recommend you go with the X-Dragon over this product, if only because of the SunJack’s unnecessary extra bulk.