Solar Phone Chargers

A SunJack solar phone charger is a foldable ETFE solar panel with USB-C and USB-A ports that charges your phone straight from the sun, no battery required. Each portable solar charger here is weatherproof, folds to tablet size, and clips to a pack, so a solar panel charger for phone use works on the trail, at camp or during an outage.

6 Produkte

How fast does a solar phone charger work?

The figures below assume full, direct sun with the panel facing it, a typical phone with a 3,000 to 4,500mAh battery (about 11 to 17Wh), and the usual real-world output of about 60 to 70 percent of a panel's rated watts. Clouds, haze, early or late sun and a panel lying flat all slow it down.

PanelRated outputUSB portsPhone charges per hour of sunWeight
15 Watt15WUSB-C 5V/3A, USB-A 5V/3AAbout 0.6 to 0.9, so one full phone in roughly 1.5 to 2 hours1.4 lbs
25 Watt25WUSB-C 5V/3A, USB-A 5V/3AAbout 1 full phone per hour, or two phones at once at a slower rate1.7 lbs
40 Watt40WUSB-C PD 30W, USB-A 18W, DC5521 21VAbout 1 to 1.5, limited by how much power the phone accepts; also charges a tablet or power bank at the same time3.5 lbs

A phone only draws what it can accept, usually 15 to 27W, so on a single phone the 25 Watt and 40 Watt panels are not much faster than the 15 Watt. The extra watts matter when you charge two devices or a power bank. More on this in how many watts you need to charge a phone with solar.

Which solar phone charger should you get?

Hiking and day trips: the 15 Watt or 25 Watt. Both fold to tablet size, clip to a pack with the included carabiners, and have USB-C and USB-A ports. The 25 Watt charges two phones at once.

Multi-day trips or two devices: the 40 Watt. Its USB-C PD 30W port charges a phone at full speed while the USB-A port handles a second device, and the kickstands keep it angled at the sun.

Keep charging after dark: add a power bank. The 10,000mAh power bank holds about four to five phone charges and refills from the 15 Watt or 25 Watt panel in an afternoon. The 100W 25,600mAh power bank holds about eight phone charges and can also run a laptop. The 15 Watt and 25 Watt panels come with the 10,000mAh bank as a kit option, and the 40 Watt + 100W power bank kit bundles the big one. All kits are on the solar panel kits with batteries page.

Solar phone charger FAQ

Does it work in clouds or shade?

It works, but slowly. Light cloud can cut output by half or more, and full shade produces very little. The 40 Watt's USB-C PD port holds a steadier connection in low light because it charges at a higher voltage. If you often charge in poor light, charge a power bank whenever the sun is out and charge the phone from the bank.

Can it charge a phone directly, or does it need a battery?

It charges directly. Plug the phone into the panel's USB port and set the panel in the sun. A built-in smart chip matches the charging speed to the phone and protects against short circuit, over-voltage and over-current. A battery is optional and is for charging at night or storing power for later.

Is it waterproof?

The panels are weatherproof. The cells are sealed under an ETFE layer, the USB ports are rated IP67, and the junction box is silicone bonded to the panel. Rain, snow and dust are fine; do not submerge the panel or leave a phone out in the rain while it charges.

Will it charge an iPhone and Android?

Yes. The ports are standard USB-C and USB-A, so any phone charges with its own cable. The 15 Watt and 25 Watt put out 5V at up to 3A per port; the 40 Watt's USB-C port supports Power Delivery up to 30W.

Going ultralight? See the backpacking solar chargers. Need a panel plus battery in one box? See the solar panel kits with batteries.