device chargers that use lithium AA’s

That Energizer one will charge your average smart phone in about 6-8 hours, one time. I have a 4000MaH thin charger from Verizon that is the same size and weight as my phone that will charge it from full dead in about 45 minutes, but again only once. I don't think the battery powered ones are worth the time in my opinion, but again, it depends on how long and how far you are from power.

You have misinterpretted what has been said on the other threads regarding the Miller charger/power supply (mentioned in the inReach thread). It is DEFINITELY NOT an AA battery charger like the Energizer.

The Miller Charger is made to use a single Lithium rechargeable 18650 battery. This is a 3.7 V 3400 mAh battery that is quite large compared to an AA battery. You can't buy a disposable version of this battery (at least I'm not aware of one).

The Miller charger with the single 18650 can charge my iPhone twice or my inReach once.

I wonder if there is another device charger that uses _four_ lithium primary batteries instead of three. If so, I wonder if the higher voltage would do anything disruptive in the device battery.

–B.G.–

Thanks, Mike. That's exactly the kind of info I was looking for. In the picture it looked like a AA, so I thought they were the same size.

Have you looked into the various lithium ion chemistries?

The 18650 3400mah battery mentioned is a good one. However there are various sizes of batteries available for charging USB devices. As big as you need there's no limit and they're all very efficient for the weight.

Furthermore there are other devices for charging including the 2 ounce Brunton hydrogen reactor which puts a 10,000mah li ion to shame in terms of efficiency per pound.

There are also solar chargers and Peltier chargers available in the 10,000mah Li ion weight range. Examples of these are the flamestower
or a hand generator.

The cobalt chemistry (ICR) Li ion batteries are the most efficient option per pound until you get into hydrogen reactors or over 10,000mah of power demand.

It is very easy to build your own 5v micro USB regulator as well and use any 3.7v Li ion cell you wish on the diy route.

Adam,

I use a similar setup to the below and it comes in at ~7oz. If you don't need that much capacity, you can take only 1-2 18650's or get a battery bank that only fits 1 or 2.

http://tinyurl.com/n4cr8nr

Furthermore there are other devices for charging including the 2 ounce Brunton hydrogen reactor which puts a 10,000mah li ion to shame in terms of efficiency per pound.

According to Brunton:
  146g Reactor, 242g with Hydrogen Core

242 grams is 8.5 ounces. That’s what you have to carry to recharge anything.

Each Brunton hydrogen core delivers 4500 mAh at 5 volts, or 22,500 mWh, or ~93 mWh per gram of carried weight.

The combination of Miller charger and Panasonic 18650 battery delivers about 3400 mAh at 3.6 volts (slightly less due to conversion loss), or 12,240 mWh, or ~156 mWh per gram of carried weight.

There are also solar chargers and Peltier chargers available in the 10,000mah Li ion weight range. Examples of these are the flamestower or a hand generator.

The Flamestower is really impractical:
  … it will take three hours to completely charge your phone with FlameStower.

So you get to carry a 10 ounce charger that needs three hours of sitting in a hot fire (plus adding cooling water), to charge a phone, once?

Am I missing something?

— Rex

I have yet to find anything simpler, more reliable, better performing or cheaper than Jackery external batteries.

The Bar is 5400 mAh, 5.4 oz, $29 and will charge an iPhone 5 ~2.5 times.
The Giant+ is 12,000 mAh, 10.4 oz $49 and will charge an iPhone 5 just over 6 times.

I use the Bar for backpacking and the Giant+ for kayaking. Combined with keeping the phone in Airplane mode when not needed, the Bar will keep me charged for over 12 days.

I am not affiliated with Jackery…I just like an use their products.

Sorry my numbers were off. It looks like you're best off carrying up to 10,000 mah USB external batteries period.

Darn interwebs misinformed me on reactor weight.

The 18650 is what a lot of ecigarette users are carrying around. It is hard to beat unless you need more than 10,000 mah.

There are lighter more efficient lithium polymer cells that can hold more amp hours but they run in a series circuit to lower the drain across that type of very low draw chemistry. This is where you'd have to DIY a charger to get ahead of the 18650 cobalt chemistry cell at 3.7v.

I don't know of a commercially available option that uses higher capacity lower draw cells in series to accomplish this feat. By the time you regulate the voltage down that far at a full charge it would end up pretty close. You'd certainly have to run at least two 2600mah lipoly cells to get ahead of two 3400mah ICR Li ion 18650s. Even then I don't know if you'd even benefit.

I run higher voltage charger that I built but it uses much larger cells than were talking here to benefit me over 3.7v cells.

In short run 3.7v up to 5000mah and carry up to 10,000mah before looking into more complex alternative.

I still like the flamestower at 10 ounces for reading on a Kindle by the fire… If it works lol isn't out yet. It has merit over carrying light for a book versus a reader plugged into your fire though potentially.

Charging a cell off of a cell really cuts your cycles in half. Not very green of us to do so.

That's the part I forgot to mention trying to weigh all your options.