- By Prateek Levi
- Sun, 06 Jul 2025 06:02 PM (IST)
- Source:JND
If you're always on the go and can't bear to have your phone run out, a power bank is more than a useful trick—it's an everyday must. But not all power banks are created equal. Selecting the best one takes more than simply choosing the largest battery or the lowest price. From voltage suitability to protection mechanisms, here's what you should actually be looking for before you buy.
Look at the Voltage Output
Each device charges at a certain voltage—most contemporary smartphones charge at 5V, but some charge higher voltages. The catch? Not all power banks are designed to accommodate these differences. If the power bank outputs less voltage than your device requires, charging will be excruciatingly slow or won't occur at all.
So prior to purchasing, cross-check the voltage output of the power bank with your phone's charging specifications. This information tends to be printed on your phone's charger or found within your phone's settings.
Know Charging Capacity
The ideal power bank would recharge your phone to its full capacity at least once. To achieve this, start by checking how much battery capacity your phone has (this is indicated in mAh within the settings or on the website). Next, find a power bank with a capacity of double or triple that amount.
For instance, if your phone features a 4,000 mAh battery, opt for a power bank of no less than 8,000–12,000 mAh capacity to have more than enough juice to last you multiple charges.
Emphasise Safety Features
This is where you should not skimp. Low-cost or shoddy-built power banks might ruin your devices—or worse, be a fire hazard. Always ensure that the power bank features internal protections against overcharging, overheating, and short circuits.
Seek out safety features such as:
- Auto shut-off when the unit is fully charged
- Circuit protection
- Over-voltage and short-circuit prevention
- A power bank without these simply isn't worth the risk.
Know What's Inside: Battery Type Matters
The battery type used within a power bank has a direct impact on its safety as well as how well it works. Low-end devices might employ inferior battery cells which tend to leak or even explode in the long run.
For peace of mind, opt for power banks based on Lithium-ion (Li-ion) or Lithium-polymer (Li-Po) cells and are BIS-certified (Bureau of Indian Standards). These may cost a bit more, but they're much safer and better in the long run.
Check the Ports—And How Many There Are
Charging more than one device? Then don't forget the number and type of ports. Some power banks only have a single output port, meaning you're stuck charging one device at a time. Others might have two or three.
Also, look and see if the ports are compatible with the charging cables that you already have—USB-A, USB-C, or Lightning.
Build Quality Makes a Difference
As power banks are meant to travel with you—usually thrust in pockets or bags—they have to be robust enough to endure regular wear and tear. A weak body is a danger to your safety and won't last long.
Opt for power banks that have quality plastic or aluminium casing. Not only do they look more premium, but they also provide superior protection from dust, water, and accidental drops.
Don't Skip the Power Indicator
A tiny detail, but a significant one. Power indicators—whether a mini screen displaying battery percentage or plain LED dots—allow you to have a clue about how much juice is left in your power bank and when it's time to recharge.
It also saves you from inadvertently draining the power bank while you're away from a wall outlet—or overcharging it when it's plugged in.
Final Word
A power bank is more than a reserve charger—it's your reliable buddy for your daily grind or road trip day. But selecting the right one entails looking beyond capacity and cost alone. Compatibility of voltage, safety levels, battery chemistry, port type, and even casing material all contribute to how effectively it will work for you.
Take a few minutes to check these boxes before buying—and your devices (and your safety) will thank you.
