I have very little technical knowledge about electronics and batteries, how they charge, etc. Please educate me. Apologies for the long post.
I have seen discussions of fairly lightweight AA device chargers in a few threads. Specifically, these two:
Energizer, 45g for charger, runs off of 3 AA's (possibly discontinued?): http://www.amazon.com/gp/product/B0093GIME8/ref=ox_sc_act_title_2?ie=UTF8&psc=1&smid=A1IHGAQ4WOI71D
Miller, 32g for charger, runs off of one AA: http://www.fasttech.com/products/0/10001919/1137904-miller-ml-102-universal-usb-smart-charger-version
What are the pro's and con's of these two? For example, I'm reading in the inReach SE thread that the Miller has the amperage to charge the inReach but the Energizer one does not. Will either work with pretty much any smartphone (if you have the right cable or adapter)? What about other devices that charge from USB but have different requirements, like headlamps, iPads, Kindles, Steripens, and so on?
What is the difference between the kinds of lithium AA's that these two chargers can use to top off electronic devices? Weight? Capacity? Reliability? Rechargeability?
The Miller one can charge rechargeable batteries in addition to using those batteries to charge other devices. How do the batteries you can charge with this Miller device compare to the Energizer lithium AA's you commonly see at RadioShack (other than the fact that one is rechargeable and one is not)?
Are there better chargers out there in this same weight range?
What are the advantages/disadvantages of these chargers that run off of lithium AA's compared to external batteries that you charge from a wall socket (other than weight differences, and the use of AA batteries vs. AC charging)? Obviously depending on how long you'll be away from AC, the decision might be fairly obvious unless you want to carry solar panels. But what considerations are there other than that?
Right now I have the Energizer charger and a Lightning adapter to charge my iPhone with Energizer Ultimate Lithium AA's. I also have an inReach for Smartphone (which itself uses lithium AA's). But at some point I could see myself taking an inReach SE, a Steripen Freedom, maybe a Kindle, or some other sort of USB-charging device. And when I travel other than backpacking I take an iPad. Haven't tried the Energizer charger with the iPad.
At home I use one of these during power outages: