Buyers' guide: Power bank for your smartphone
I want to buy a power bank to charge my mobile devices, but I'm confused about the technology, brands and pricing. Need your help urgently to help me make a right choice.
— Shraddha Choudhury, Vishwas Naik, Aidan Pereira
Before you buy a powerbank — aka portable battery charger — check for the mAh capacity mentioned on your smartphone battery or the specs in your mobile's manual (in the case of non-removable batteries). For instance, if your device has a 2000mAh battery capacity, buy a power bank with at least 2500mAh. If you buy a 4500mAh model, it means you can charge your 2000mAh phone at least twice. In any case, opt for the highest capacity that your budget allows.
Also check 'current draw'. Older phones do not draw more than 1 Ampere to charge their batteries. However, newer handsets and tablets need a 2.1 Ampere input current. Check your mobile's original plug for details on current draw. If possible, buy a powerbank with two USB ports — 1A and 2.1A. Remember: When it comes to charging your gadgets, current draw is more important than capacity.
Essentially, pay attention to the type of cells — Lithium-ion or Lithium-polymer — used in the power bank. Li-ion is cheap and easily available. Li-poly cells, on the other hand, are more expensive, but provide twice as much charge density per unit weight.
Ensure that you buy from a reputed brand. Low-quality lithium-ion power banks not only effect performance, but are also a potential hazard. Many times, cheap battery packs — the type available on the streets — do not list the correct mAh capacity or the proper current draw. These batteries could also explode due to heating from over charging. For improved safety and performance, buy a model that comes with over voltage protection (OVP), over charge protection (OCP) and over-temperature protection (OTP) that ensure its longevity against spurts in current, and over heating during charging and discharging.
Can consider these ...
* Mi Power Bank (Rs 999): 10400mAh; L-ion; 2.1A (and 1A through single USB); OVP, OCP and OTP
* Adata PV110 (Rs 2,450): 10400mAh; Li-ion; 1A and 2.1A; OVP, OCP and OTP
* Portronics Charge 2 (Rs 2,900): 12000mAh; Li-ion; 1A and 2.1A; OVP, OCP and OTP
If you're looking for something over and above a plain power bank, you can consider these ...
* Adata DashDrive Air AE400 (Rs 4,500): This device comes with a 5000mAh battery to recharge your devices. Besides, it can connect to existing wireless networks and create an internet bridge connection for up to 10 other devices. You also get a USB port that takes input from pen drives and hard drives, as well as a MicroSD card slot, allowing you to share this storage wirelessly.
* JBL Charge (Rs 6,500): This is a Bluetooth speaker that boasts of a 12-hour playback time and frequency range of 150 20000Hz. Why is it listed here? Its 6000mAh Li-ion battery can also charge your smartphones via its USB port.