“EasyAcc PB3350CS Powerbank Review”
Sorry for the delay of this one, I actually had the review for some time but haven’t had the time to upload it. Found this powerbank on Amazon as one of the daily deals, for just $6.99 it seemed like a good deal and I couldn’t pass it. This is going to be a short review because there is really not much to talk about it. 
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Details and spec:
-Price and link: $6.99 http://www.amazon.com/dp/B01423C81Y
-Rated capacity: 3,350mAh, 3.7V
-Rated input/output: 5V 2A / 5V 1A
-Weight & size: 71g, 101x 24x 24mm
-Ports: 1x USB out, 1x microUSB in
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Aesthetic and build quality:
Same as the previous reviewed powerbank, it came in a simple cardboard box. This package is being used on so many gadgets now, and I prefer this a lot more over the conventional color printed box. It comes with a user manual and a short microUSB cable.
It feels quite well built, the plastic has matte finish and does not immediately scream cheap when held. It uses a single button to turn on and check the battery level, which is displayed in 4 blue LEDs.
In the back we get some details: it’s curious how they decided to show the energy (Wh) in full details by just multiplying voltage x capacity. Even if the circuity was 100% efficient, a 3,350mAh battery will very unlikely yield all of that capacity. Most manufacturers use Min/Typ rating and 3.6V volt, since the battery is not discharged in full.
The size is roughly the same as the S2+.
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Operation and Performance:
-This powerbank is operated by a single button, does not have automatic turn on.
-Will shut down after 10 seconds if the load is <150mA.
–4 blue LEDs shows the battery charge level.
-Default coding is Apple 1A as shown by my YZXstudio meter. By connecting a smart device, it will only pull 1A. But because my USB load is just a dumb load, it can ignore the coding and pull more than that.
Following chart shows discharge tests at 0.5A, 1A and 1.5A. Didn’t test 2A because that would be too much load on a single cell:
As you may have expected, the highest efficiency is achieved with the lowest load. I got lower than usual efficiency at 1A so I tested it repeatedly, however I got the same result from all tests. 78.7% efficiency at 1A is not too bad for a single cell, and at 1.5A 67% is a bit alarming. But in real use you won’t see this because the output is limited at 1A when connecting a smartphone.
Observations:
-They advertise 120% of charge for an iPhone 6, and I can confirm this is true. I got 9.78Wh at 1A which is rougly 1.14 times the energy needed to charge an i6 (~8.5Wh).
-The boost driver in this unit was able to maintain a healthy voltage until exhaustion. This means you will always get the same steady charge rate.
-Note that my efficiency rating is based on what they advertise, I doubt the battery is really 12.39Wh so the real efficiency should higher. (a Sanyo GA is only 12.8Wh at very low discharge rate)
-To recharge it back, it took 3hr 7min and 12.19Wh from a 5V 2A source. About the same time it takes to charge an 18650.
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Veredict:
Considering the price and the fact that this is a single cell powerbank, I would say the performance is more than acceptable. Being able to provide a full charge to a modern smartphone on the go while being compact enough to carry without being noticed is a big plus. If you can get this for the same price I did ($6.99) then I would definitely get one, but at the current price of $9.99… no so much. I rate this 7/10.