Portable power banks are the latest utility gadgets primarily for the smartphones which have gained tremendous popularity exploiting the lack of enough battery power in the contemporary smartphones and tablet PCs. Basically, a portable charger is a sophisticatedly encased rechargeable battery cell, which can retain high energy within it and from which via USB cables you can charge up your smart phones, when you need to charge. But there are many important aspects which are needed to be clarified before zeroing on any of the best portable power banks.
Capacity of the portable power bank: Capacity, as can be easily presumed, is used to determine the amount of charge the portable power bank can retain within itself and can deliver at the time of need. It is measured in mAh unit. The more the measure, the more is the ability of the portable charger to charge up your android smartphone.
Yet, there is a common misunderstanding regarding the capacity potential of a portable power bank as it is perceived that the claimed power by the manufacturer is the actual deliverable power. To put it simply, a certain portable charger with 5000 mAh labeled capacity would never be able to covert whole of its contained power completely due to some obvious losses. Thus it is found most of the external battery packs in general becomes efficient upto 80% of their maximum marked capacity.
Current ratings: The matter whether a portable charger would be charging your smartphone fast and even that if it is going to get charged itself fast enough is dependent on the input and output current rating. The higher the rating, the faster it would charge. In general, there are two sorts of rating available one being 2.1 A at 5V and another being 1A at 5V. The exact details for each portable power bank can be obtained from the concomitant specifications or the relevant power bank review.
Number of USB Ports: We often find the need to charge more than one devices simultaneously. This need can be satisfied with the provisions in the portable chargers which provides more than one USB ports.
Portability aspect: Portable Power banks are better of course if they have greater capacity but with big capacity, portable chargers become bulkier and harder to carry along, which is a genuine trouble. To get rid of this problem, it is better to confine the choice within the small capacity portable chargers.
Budget and Branding: There are a lot of fake, cheap power banks available in the market so it is better to keep the budget up to a considerable amount (around $15) so that you can avoid the unbranded counterfeit portable chargers.
Battery cell types: There are basically two types of portable power bank battery cells, namely one is Li-ion which are old generation, the other being Li-poly, the new edge one, being sleeker, safer and also tagged with high price in comparison to Li-ion.
Safety Matter: the matter of safety protection could not be emphasized more when it comes to portable chargers which are basically bare battery cells, encased. So better to check if the portable power bank that one is about to choose is providing all the standard safety procedures like short circuit protection, over charging protection and other standard measures.