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triciasurfer
June 11th, 2015, 07:14 PM
I received a power bank. All 6 sides of the power bank has no writing. I'd like to know how much power it can hold (mAh) and how powerful it can flow out (mA). How can I find out these 2 bits of information?
tgalati4
June 12th, 2015, 04:43 AM
You can install a battery monitor app on your smart phone and plug it in and run it for a day or two. The app will integrate the power over time and give you an idea of amperage and total power capacity.

Post a picture of it. Perhaps someone has something similar and can give you an idea of its capacity.
triciasurfer
June 18th, 2015, 01:01 AM
tgalati4,
Here are pics of what I was given.
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tgalati4
June 18th, 2015, 05:20 AM
Looks similar to this: http://www.frys.com/product/8323447

My guess is 2600 mAh with 1 amp charge and discharge. The real test is how well it works with your phone.
triciasurfer
June 18th, 2015, 05:28 AM
tgalati4,
thanks again for your reply.
That Fry's powerbank has a listed 500-cycle maximum. Yikes! I'll make sure to use my powerbanks only when I really need to. I used the Ampere app (https://play.google.com/store/apps/details?id=com.gombosdev.ampere) to test. The "battery charging" icon in the display is either red with an X on the battery, indicating lower-power charging; or a black and white icon, indicating higher-powered charging. I get the red icon when I charge by connecting to a USB port. I get the black and white icon when I charge with the supplied Samsung power adapter.

When I plug in the powerbank, I get the black and white icon. But, according to Ampere, the charging is rather low. Not 1A and up (what the Samsung adapter is supposed to produce), but more like 200 mA.

Anyway, these were free gifts.
tgalati4
June 18th, 2015, 03:21 PM
Most lithium ion batteries are only good for 300 to 500 charge-discharge cycles. That is why laptop batteries fail so often. Use it every day and you will only get a couple of years out of it. USB ports generally only put out 500 mA, so anything higher is a bonus. The batteries power circuitry will limit the current to whatever it is designed to put out.