Most of us do carry our fair share of gadgets, where a smart phone is a definite “must have” device, while some of us augment that with a tablet for those moments where lugging around a notebook is just too much trouble. An iPhone External Battery is indeed at this moment. If you’ve ever watched your phone’s battery die before you could charge it again, you know a good, portable battery pack is a lifesaver. So this passage will tell you some details you need concern. Here i provide something i collect for you.
Read This Before You Buy A Power Bank– Power Bank Specifications
1. Capacity: 2000mAh-26,000mAh,
2. Battery type: A Lithium Polymer 18650 is the most used, You can also see solar power bank and solar charger in the market.
3. Material: ABS Etc
4. Port:1-4 ports
5. Power efficiency: most of the power bank are 70%–90%
6. Cycle life: ≥500 times
7. Input: DC 1A-5V /Output: DC 1A-5V (Some Power Bank Support Quick Charge Tech)
8. Color: Blue, Pink, Black, Silver, Etc.
9. Product Size: lenght*width*height MM
10. Package Size: lenght*width*height MM
11. Net Weight: From 100G to 500G
12. Gross Weight: 100-337G
Parameters
Different brands of power bank have different electric parameters:
Firstly, the charge voltage and current
Secondly, battery capacity.
Generally, the battery’s capacity is proportional to its size. The higher capacity, the bigger size.
Thirdly, output voltage and output current.
Output voltage must be 5V. Discharge current theory is also to the bigger the better, charging will be quicker. But the actual problems should be paid attention to the digital products’ features and heat problems.
Forthly, protection parameters.
Power bank should have protection measures of over voltage, over current, less voltage etc.
These parameters of power bank decide its charge speed, charging time and use security and has the very big relations to everybody everyday use.
Appearance
We believes that appearance is first factor a lot of friends will choose. Fashionable appearance can bring a lot of fun.
Related:
Where to buy a reliable power bank
Before You Buy a New iPhone, Read This
Read This Before You Buy An Earphone
Tips: If you have something to add to this story please share and make a comments.
blog.easyacc.com 
If my phone battery is 4000 mAh what power bank should I purchase? How can I charge my phone and digital camera at the same time?
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Hi Supratik, you need a power bank with 2 output port at least, and considering the battery capacity of 4000 mAh, you’d better choose a 10000 mAh power bank to sustain more than 1 recharge cycle for your phone and camera. EasyAcc slim 10000 mAh power bank is a good candidate.
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