What think ye of the Solio Bolt?

The solio website has the specs that you quote:

Max Wattage: 5 Watts
Discharge Rate: Fixed 5V, 1,000mAh
Charge Rate: 5-5.5V 450mAh
Charge Time via USB port/wall charger: 4 hours 30 min.
Charge Time via Sun: 8-10 hours

However, their specs are using goofy units and it is good to know the correct units and what they mean.

Power is in watts, calculated by the current times the voltage. The Bolt can deliver _up_to_ 1000 [milliamps] X 5 [volts] = 5 [watts].

How long can it keep this up? That would be a measure of how much energy it can store. Energy is in joules, calculated by the power in watts times time in seconds. A more useful unit for energy is watt-hours which is joules/3600. The Bolt specs say the output is 1000mAh at 5V which suggests it can deliver 5 [watts] X 1 [hour] = 5 [watt-hours].

According to the website, the Bolt will charge your phone in 3 hours because it delivers 1 amp, just like a wall charger. That suggests it has 5 [watts] X 3 [hours] = 15 [watt-hours] of energy stored.

Which is correct? The answer is in the Li-Ion battery specs: 3.7 volts, 2000mAh. That is 7.4 watt-hours. The conversion to 5V is likely about 85% efficient if they did it right so the watt-hours you get at 5 volts is 6.3 watt-hours, closer to the 1000mAh @ 5V = 5 watt-hours spec. So 6 [Wh] is a spec I would use.

This means the Bolt doesn't charge your phone at 1 amp since it takes 3 hours. More like 333mA of current.

This also means you get only one recharge of your phone to completely deplete the Bolt. This makes sense because an iPhone for example has a 3.7V 1420mAh battery (5.25 watt-hours) compared to the Bolt's 6 watt-hours.

My take-away:

In direct sun, the Bolt takes 8-10 hours to charge. So if the weather is perfect and your "sundial" pencil indicates you are pointing perfectly, then an entire day of perfection will charge your phone once. I think you will get at best 1/3 of a day's charging in good weather just because you can't keep it pointed well. So anticipate charging your phone every three days, best case.

What this exercise indicates to me is two things: You need a lot more solar panel area out there, arranged at a few different angles (I estimate about 2 sq. feet). And, you need a bigger battery to hold you over through inclement weather (I like a 24 watt-hour Li-Ion battery). Unfortunately, I haven't found such a beast in a convenient package with a strong focus on lightweight. The battery alone weighs 5.5 ounces, so everything else should be ALAP. Also, it would be nice for such a setup to charge AAs and AAAs.

I am working on repackaging and beefing up of a Bolt and of a Powerfilm USB+AA solar setup. Hope to have something soon.

Edit to remove junk text

Well thought out and well said!
Let me know how your retooling goes.

I just bought one today and it's charging as I type. I'll be taking it with me on a two night backpacking trip this coming weekend so I'll let you know how it works out for me when I get back. I came home with the Brunton Restore Hybrid Solar Charger this morning, and that one would not charge any of my apple devices despite being labled for such, so back to the store it went. I got the Solio based on the recommendation of one of the employees at REI. Her friend has one and they were able to charge all their devices with it. She did say it doesn't charge very well when you are hiking if you are in and out of the shade, but once in camp in the sun it charged great.

You need to be careful of USB charging because this usually does not specify the amperage delivered but rather the voltage. You need to establish both measurements to work out if it has a chance of charging many smart phones etc. Most smart phones need 500ma or more (especially Apple) for the charging to even have a chance of it working. This seems to be an issue when charging most Li batteries.

I have a Power Traveller – Explorer (78 grams) setup which works quite well. You can connect up to 3 solar panels (78 grams each) into the changer/battery pod to speed charging each panel producing 200ma at peak. This isn't something detailed on the web site but is confirmed by their support people.

Using a solar charger system in the Pyrenees I found it easiest to set up when I stopped in the middle of the day for lunch and a siesta but had reasonable success with it strapped across the top of my pack. It worked to keep a HTC smart phone powered up along with 123As for my steripen. I also have a Power Chimp (20 grams) for charging AAA/AA batteries using the same solar panel which keeps my Foretrex 401 and Petzl Tikka 2 XP running.

The Power Chimp system worked well on the Australian Alps Walking Track where it is 14 days between access to the power grid.

Hey Laurie, How did your Solio Bolt work? I am considering one and would like to hear how it worked for you.

thx-chad

I want to read some personal reviews of this thing, too!

My son, 5 days on the JMT today, texted me (with our inReach) that he wants me to bring him something stronger than the Solio Bolt when I resupply him at Florence.

He has been diligently setting it at the sun whenever stopped, and wearing it on top of his pack while hiking. He has been able to recharge his iPhone 30% at most each day. That and it weighs far too much.

Not sure what I will get him. I have been working on a MyoCharger, but am too busy to finish it before he needs it.

As I posted in the other thread, I've tried just about everything including this one.The Bolt is crazy low powered and was never able to charge my Droid Bionic over 40-50%. This is far from the best option out there IMO and even the best are sketchy at best.

Saw some info that newer thin (bendable) solar panels that will ALSO utilize infra red spectrum rays is in the beta testing stages. It was in a boating magazine (I forget) and showed roughly 1' x 1' panels.

The infra red capabliity was said to increase voltage by 25%.

Amorphous silicon cells have been around for a long time. They tend to be cheaper and lower maximum output. Besides, I don't think that you want to increase the cell voltage by 25%. Maybe amperage or maybe efficiency.

It sounds like the marketeers have been busy again.

–B.G.–

I used a Solio Bolt on a recent 10 day hike in northern New Mexico, I had no problem charging my iPhone or another participants camera. Unit was fully charged via outlet when we started and then recharged along the way, either by sitting in the sun at camp or strapped to the top of my pack. Worked like a charm for me, liked the versatility of the USB connection. Only concern was for unprotected solar panel, would like to have a way to protect 2nd/exposed panel from damage when stored in pack.