Power Bank Buying Guide

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Capable smartphone processors, large bright displays, endless gaming sessions and 4G/3G Internet connections drain power from your smartphone or tablet’s battery in no time and make an additional external battery bank a necessity. A power bank is also very handy for those long flights, long commutes or simply for any of those times when you have to rely on your smartphone, tablet or laptop for hours.

We cut to the chase and offer you 5 one-minute essentials you need to know before buying a power bank.

# 1 Power bank capacity – understanding the MaH

The charging power of power banks is measured in 1000 Mah (Milli Ampere Hours). The capacity of your phone’s battery as well as the powerbank both is measured in MaH. The larger the MaH number more times the power bank can charge your phone. For a detailed analysis of what powerbank capacity you can expect in real-world from your powerbanks, have a look at our guide that explains Powerbank capacity . Power banks are available  in the market in four rough capacities –

3200-3500 mAH  About one charge

$8 to $15

These are ultra portable power banks that are often very small – sometimes just lipstick sized.  They are also very slim and easily pocketable. Price is between $8-$15 depending on features.

Such power banks will mostly charge your phone one time. If you plan to buy a ultra portable power bank, we recommend that you go for the highest capacity as the phone batteries are becoming larger in latest phones and 3500 mAH is barely enough for some of the latest phones.

Buy slim not round – Slim power banks are better than round thick ones as they are easily pocketable in jeans and jacket pockets. You can also store them in same pocket as the smartphone and charge your phone on the go.

Not for tablets – Such ultra portables will not even give half recharge to a typical tablets and hence are suited only for slim and light smartphones with battery capacities  up to 2500 mAH.

Slim ultra light mobile power banks are a great choice as ultra-light accessories for  iPhone 6s iPhone 6 and Moto X series as well as ultra-light Samsung Galaxy 6 or 7 devices.

5200-6700 mAH – About two full charges

These medium sized power banks give about two charges and cost about $10 to $20 depending on the features.

We recommend buying slim largest capacity medium sized power banks with fast charging feature.

Such external battery packs will give one full charge to most tablets and are the smallest suitable mobile battery banks for tablets.


10,000-16,000 mAH – 3-4 full charges


20,000 to 26800 mAH – 5-10 full charges

These huge power banks may look very tempting but the massive weight makes them a liability in many travel, flight and commute situations. they are perfect for camping, keeping for long car journeys and as a back up at home in case of hurricanes etc.

Again we recommend buying slim ultra-large power banks but only if you plan to carry them in flights.

For car, emergency use the better approach is to buy the biggest capacity that you can buy in your budget regardless of the size.

We highly recommend buying powerbank with USB-C PD ports, or direct DC laptop charging function or AC wall outlet function and/or car jumpstart functions if you plan to go for ultra-large power banks above 20,000  mAH.

27000 mAH to 60000 mah – 6-20+ full charges

These are heavy high capacity power banks intended mostly for emergency backup of AC backup as well as travel and car use.


2 Size – Small, Large or extra large power bank

Size and weight of a powerbank are very important factors



Power bank for phone, tablet or laptop or  all the three?


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