I recently bought a Anker supposed 14 watt 5V out solar panel that uses USB connectors and cables for it’s power output. To go with it I have wanted to get a couple of USB powered battery chargers with reasonably decent electronics. The first I bought is a two slot AA and AAA NiMH charger called the Maha Duo 9000. This is a Korea made charger and NOT from Maha Powerex, the USA company. It does though seem to be a good quality true independent dual channel NiMH charger, microprocessor controlled. Below is my link to my impressions of it.
XTAR also makes three 5V USB powered chargers, two for Lithium Ion and one with dual capability, NiMH & Lithium Ion. These are the MC2, the MP1S and the XP1.
The MC2 is a two slot slider type charger for standard 4.2 volt termination voltage Lithium Ion cells, supposedly good for everything from 10440 to 26650 batteries.
The MP1S is a single slot charger that is listed as covering much the same battery range but it uses included spacers to adjust for different length batteries and claims to be good all the way to 18700 length batteries but 26xxx diameter batteries are not listed so not sure if they will fit or not till I try it.
The XP1 is a dual chemistry single slot battery charger for AA and AAA NiMH batteries and short length Lithium Ion batteries. The longest Lithium Ion it is listed as compatible with is the 18500.
As all these chargers are only between $10 and $13 each from Amazon I have one of each on the way and will report on them once I have tried them all out.
If looking for a solar charging solution for both NiMH and Lithium Ion batteries this may provide what is wanted.
I like my Soshine SC-S7 UK, Review: Charger Soshine SC-S7 UK. It has a line voltage AC to DC supply, but it also works on USB power. Only one slot though.
The H2-V2 is a two slot “Universal ” charger that can handle NiMH, Lithium Ion and LiFePO4 batteries though it is best for Lithium Ion per a review by HKJ.
Additional listings for USB powered battery chargers appreciated. I realize that most removable battery USB power banks are also battery chargers but most have minimal charging info provided compared to better dedicated battery chargers and some are really designed to have batteries installed and then left in.
I had problems with my Sanyo restarting every time my solar panels dropped in output due to clouds obscuring the sun. This caused it to not terminate properly when the batteries were full and the eneloops it was charging got VERY HOT. I was using a Goal Zero which had the Goal 10+ battery pack so I connected the panel to the Goal 10 charger and then the Sanyo charger to the Goal 10. This provided a stable output and the Sanyo terminated charging properly. Now clearly I wouldn’t use this method for charging NiMH batteries but the same principle applies to lithium batteries (or at least I think it does) where the charger may overcharge the battery because it keeps restarting. In any case when I charged an 18650 with a Miller 102 connect to the Goal 10 it terminated with the battery coming off at 4.19.