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SunJack Portable 20W Solar Charger and Battery Review

Recharging our batteries with the Sunjack Portable Solar Charger
Recharging our batteries with the SunJack 20W Portable Solar Charger

While I’ve given up on using solar chargers to recharge my batteries on east coast backpacking trips because there are too many trees in the way, they’re still a great portable energy solution for car camping trips and stationary camp sites. My wife likes to car camp and she likes bringing her “devices”, so we’re always in need of off-the-grid power.

While solar power is limited by the availability of sunlight, we usually get enough sunshine on our car camping trips justify bringing a solar power panel along. One product we’ve had good luck with last year is the SunJack 20 Watt Solar Panel Charger which comes with 2 x 8000 mAh fast charging batteries. We are able to get a full charge in just 6 hours, making the SunJack a viable solution for our needs.

When we go car camping, my wife and I bring our iPads along, smart phones, and a cellular-based wifi modem, in addition to a USB-powered lantern and USB rechargeable headlamps. But, we can only last about two days without recharging our batteries (no I don’t work constantly). This is a pain when we’re at a primitive campsite because it means a visit to town and a few hours spent hanging out at a cafe and hogging their wall outlets. Anecdotally, I can recharge my iPad up to 80% power from one of the 8000 mAh SunJack batteries and a smartphone several times.

The two fast charging SunJack batteries fit into a mesh pocket on the back of the Solar Panels
The two fast charging SunJack batteries fit into a mesh pocket on the back of the Solar Panels

The SunJack 20 Watt product includes four solar panels (each the size of a Kindle), two fast charging batteries, two USB cords, and a power splitter so you can charge two batteries at once. The batteries are capable of powering 5V devices including iPads, smartphones, and Kindles, but not a laptop. Each battery also has two USB output jacks and one input jack so you can recharge two devices simultaneously while recharging the battery, which is awesome when we’re in camp.

The lithium-ion batteries and cables provided with the SunJack 20W are also faster changing than the other USB batteries I own because they’re rated for 2 amps instead of 1 amp. I’ve tried switching in different USB batteries and different USB cords I own, but they take over twice as long to charge.

The benefit of having the pair of batteries hooked up to the solar panel is that you can store twice as much power without having to switch in a new battery. This is very handy when we’re away from camp all day. The two batteries stow away in a pocket on the back of the panel for easy storage when the unit is hung outside or folded up for storage. However, if you travel with other USB cords, you do need to be careful not to switch them with the fast-charging SunJack power cords because they are indistinguishable.

Both of the SunJack batteries must also be turned “on” when you hook them up to recharge your device. I own other regular USB batteries that also require this, so it’s not unique to SunJack. Still it’s not intuitive, so I thought I’d mention it. Each SunJack battery also has a small LED light built-in so you can use them as a flashlight at night.

Having owned the SunJack 20 Watt Solar Power solution for nearly a year, I’m surprised that it hasn’t been eclipsed by other faster charging and more powerful solutions in the market. I guess fast charging batteries and cables are a higher competitive barrier than I realized. But this solution is more than sufficient for our current car camping needs and one that I feel confident in recommending to others.

Disclosure: SunJack provided Philip Werner with a sample portable charger for this review.

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  1. I’ve been looking at these Solar Panel options since they first came out and haven’t wanted to spend my own money until I could read some decent reviews instead of the typical Marketing peoples untrustworthy Hyperbole. I wondered if the Units would work in the “Green Tunnels” of the East Coast and you say they don’t. Well they probably would if you stopped hiking every day at Noon and let recharge the afternoon away until Sunset about 2030 hrs. The ONLY Electronic Item I bring with me that would need to be recharged is a small Radio which uses two AA Batteries so the Solar Panel Options weigh more than the two Batteries so that has been ruling out a purchase. Now I would like to hear from someone on the Left Coast who has been Hiking the PCT where you do not have the Green Tunnel until you get up far North and then into Oregon and Washington. Thank you for another good honest review…

  2. Great and timely article. I’ve been thinking of getting one of these but am confused about the two batteries. Can you use with only one of the batteries or do you need both to operate the unit? In use (canoe camping), I would probably leave one home to save weight.

  3. When we kayaked the Lower Canyons of the Rio Grande Wild and Scenic River a year and a half ago, my brother in law had something similar and charged his iPhone every morning while we fixed breakfast. I was quite impressed and bought a 7W version, which isn’t nearly as impressive…

  4. Great article, very informative. We are fair weather hikers and campers and in our area it is getting really too hot for these old folks to rough it very much. Solar energy is definitely the way to go, to stay in touch, to let people know where you are, and to get help in an emergency.

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