Smartphones today, by and large, use bigger battery capacities and have much more power efficient chipsets as compared to what was standard a couple of years back. At the same time, the advancement in battery tech – faster charging, denser batteries – and associated advantages are almost nullified by consumer demands that are growing at a faster pace.
 

A simple solution is to buy a power bank or portable battery charger. But before you proceed to do so, here is what you should know.
 

Size & Power

Start by choosing the size of your battery (aka power bank). This is not just about which one will fit in your pocket or your purse. The size of the battery is about the power inside. Most batteries will feature a number on the front that tells you the number of mAh or “milliamp-hours.”

Common sizes range from 2000 mAh up to 10,000 or even 12,000 mAh. Bigger numbers mean more power, which means more recharges for your smartphone, or charging for bigger devices that need more power, like a tablet.

Though many power bank buying guides will advise you to buy the biggest possible battery capacity in your budget, we would strongly advise you to hold your horses. Some tradeoffs are also involved with bigger battery capacities.

A bigger capacity Power Bank:

• - Takes more time to charge

• - Is heavy (a problem if you have to carry it in your pockets)

• - Occupies more space, and is thus less portable

Number of USB Ports

How many devices do you need to charge? Bigger batteries (aka power banks) – with more mAh – sometimes have more than one USB port, because with all that power inside, why not share it out?

This can be useful to charge two smartphones at the same time – maybe to give a battery boost to a friend. Or you can charge your smartphone and your GoPro at the same time. Or your smartphone and your Bluetooth headset. Or even a smartphone and a tablet, if you choose a battery with enough mAh to provide all that power. With multiple ports, simultaneous charging is super-easy. If you have a USB Type-C port on your phone, by a USB Type C power bank instead of relying on adapters.
 

Charge conversion

Good power banks will offer you 75 to 85 percent charge conversion when they are new. This means if you own a 5000 mAh battery pack, it will fully charge your 3000 mAh battery phone once. Efficiency may wary depending on what charging cable you are using or charger rating you use to charge it.
 

QC or Fast Charge

Speaking of Quick Charge, does your phone support Quick Charge? If yes, don't settle for a power bank that charges at a lesser speed.

Most Power banks don't have Quick Charge (QC) on all the ports, but rather on just a single port. So, it only makes sense to check the capacity of all the ports.

Again, it becomes a dicey situation if one of the ports has QC support (preferably QC 4.0 or 3.0), but the rest are at 1A. The best bet is to settle for devices that have a mix of ports at 2.4A, 5A or with the QC symbol.
 

Brand Value

We would advise you to go with branded options, even if it means compromising a bit on battery capacity. There are several unknowns involved, like charge time, battery durability, support for fast charger, charge conversion efficiency, build quality, corrosion resistance, etc. Thus you should be better off with tried and tested options. However, at times, even the smallest of brands churn out the best products while at other times, the biggest of brands can turn out sub-par products. That’s why it’s good to peek at the review section to make the right purchase decision. Also, make sure to purchase from authorized retail stores to avoid fakes.