September 28th, 2013, 09:47 PM
Join Date: Jul 2010
Device(s): Fascinate, Droid X, Nexus 7, Note 2, S5
Thanked 807 Times in 424 Posts
Originally Posted by Puddy Tat
I did not know exactly what they were called.
My phone was released last March, so I guess by now it can be called old.
The idea of having one was if I was ever away from any AC power and needed a battery charge.
I will check out your review.
It will work as fast as using AC outlet wall charger or car charger. The spec you should be looking for is a total capacity in mAh (and compare it to the capacity of your battery to see how many times you will be able to charge your phone), and also A output of the charging port. So for example, and I will make up numbers to make an easier math, if you have a phone with 2000 mAh battery and it chargers at full speed with 1A (1000 mA) of current it will take you 2000 mAh / 1000 mA = 2h to charge it up from 0%.
So, for example if you get 6000 mAh external battery, you have to realize this is a total capacity of battery inside of the external battery case. To get to your phone it will have to be converted through 5V usb interface and back from micro-usb charging port of your phone to your internal batery. During that process you roughly loose about 30% (it's normal and all batteries do that). So you have only actually 4000 mAh capacity. Using such battery with 1A port will mean that you will be able to charge your phone like from a regular wall charger in 2h, and you can do it 2 times if you charging it from 0%.
I have reviewed a ton of different accessories here on AF, including probably close to a dozen of external power banks (batteries). That latest Astro 3 (2nd gen) uses a very efficient circuit where you lose only 20%, and you also get LED indicator (activated by shaking the battery) which gives you battery capacity in 10% increments (versus other batteries that only have 4 LED indicators for 25% increments).
If you have any other questions, don't hesitate to ask!