Here is another basic, low cost. low efficiency USB Power Bank commonly found on ebay.
USB Power Bank
Overall they’re not bad for uses such as topping up your cell phone etc.
— The first one I will review was purchased several years ago — and is now retired due to damage from a liquid getting into it. Very fortunately, it did not short the battery and ruin it. Until then it did a good job as a convenient powerbank to refill my cell phone if it got too low on power.
The solar power modules looks cool, but the output is actually very low so it would have to sit in direct full sunlight for about 50 hours to fully charge the battery. I measured the output of the solar panel at about 68 milli-amps and 4.5v max in direct sunlight therefore if you’re lost in the wilderness, sure, go ahead and use the solar panel for charging, otherwise plug it in and charge it up.
The battery inside this older one is actually a LiPo 3.7v 1S (1 cell) battery with 1900mAh printed on it.
It measures 95mm x 53mm x 12mm
I ran a discharge test on it to measure the discharge mAh @ 1.0amp and came up with 3200mAh. And this was 3 days after it had been fully charged. The voltage had dropped back to 4.0v from sitting 3 days. I discharged the battery to 3.5v (2.75v is the listed cut off voltage.)
Remember, this battery is already several years old. Apparently well over the rated 1900mAh rating.
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—— Ok and now the NEW one I just received in January of 2017 —-
So I just bought another and opened it to compare……it was $11.00 delivered.
This battery was considerably smaller. Only 10mm thick, 63mm wide and 60mm in length. (10-63-60)
However, after running the discharge test, 1.0amps the result was 3,889mAh discharged to 3.50v
Note that this new PowerBank had been charged today, whereas the other had sat for 3 days. Also this battery is new and the one above is over 2 years old with quite a few cycles on it. But these PowerBanks are good for at least 4Ah.
They list these devices as 30000mAh, 50000mAh and even 80000mAh. Does anyone know where they heck they might come up with those typs of numbers?
However, there is a TOMO USB Power Bank that I like even better because it has a digital Power readout display and uses 4 removable 18650 cells.
But they were always priced at $20 and above until recently. Now GearBest offers them at around $12.00 with FREE shipping to the USA (I just ordered one)
TOMO USB Power Bank (link is external)
(Incomplete review…will finish it over the weekend)
