Everyone has seen the USB power blocks used to add extra battery power blocks sold around town

6 months ago the ones the size of a long pack og gum were saying 2200ma

the other day I saw some that were 20,000 ma ones for 300 baht

But being in the land of scams how can you tell what is inside ? It nevers seems to be on the item only on the packaging ,

plus charging a 20,000 milliamp block must take forever and they never come with a high power charger..

anyone buy these in the last few months and have any thoughts ?

Got a few 20000 ones. All of them can't even charge my phone. Real junk, poor quality. But what do you expect in Asia. Can't buy quality.

it would be nice if there was an App that would tell how much power you had left on external power banks ,

just hook it up to your phone / tablet with the USB cable...................

It's not just the block itself. The 'correct' usb cable to make sure charging is quick. There is an app on google play that measures the input charging rate. Galaxy charging current. Many cheap usb cable can only charge 300-500mA. The better cables can charge >1000mA. But you can only test this with a unit that outputs >1000mA. The Galaxy series phones and tablet chargers usually output 2000mA. So you could bring that with you and test different usb cables for mA output.

For the battery unit itself, stick to reputable dealer from Fortunetown IT mall. Or places like bananaIT, Synnex, etc.

Edited August 20, 201510 yr by 4evermaat

I once bought a packet of Sony rechargable AA batteries from a street stall. They didn't take a charge, probably weren't even batteries at all, but at least they didn't trash my charger. Last time I bought any thing of that sort on the street, sticking with stores like Tesco.

the problem is the packaging if often so good and I think sometimes they use the same plastic injection molds and just put cheap quality bits inside to make the price lower ,

I know when I buy USB charger I make sure they are at least the 1 amp and better the 2 amp that come with top end phones , many are only half amp and it takes overnight to charge a tablet !

I have some small 1000 ma power banks that work great and were made in Japan , bought them in the USA a year or 2 ago ,

but most of the stuff I buy here is 6 months to a year tops , even the rechargeable LED flashlights do not last long

Lazada often has 30,000 mAh power packs for under B500. I have bought several (different brand names but same exact appearance) and they have worked very nicely so far.

I fly to the USA and Europe frequently and often my economy seat has no power source. I use the power packs to recharge my phone and tablet. It's especially handy if I want to watch movies or TV series on my tablet...good for the entire 12 hour+ flight. They seem to recharge in about the same amount of time that a phone does...2 to 3 hours. They get fairly warm during use but not noticeably hot. I've been using one frequently for more than a year now with no noticeable power loss.

I have never had any airport security restrict them or even look closely at them in my carry-on.

The units I'm referring to have 2 full size USB ports...one outputs more power than the other but it is not labeled so not easy to tell which is which.

They also have a built in flashlight.