Power Bank Buying Guide: mAh, Watts and What You Actually Need

Power banks are essential in Nigeria, but the numbers on the box can be confusing. Here is a simple guide to mAh, watts and ports, so you buy the right one the first time.

mAh: how much energy it stores

mAh (milliamp-hours) tells you the capacity. As a rough guide:

  • 10,000mAh - about 1.5 to 2 full phone charges. Light and easy to carry every day.
  • 20,000mAh - about 3 to 4 phone charges. A good choice for long days and travel.
  • 24,000-25,000mAh - enough to top up a phone several times, or give a laptop a meaningful charge.

Real-world charges are always a little lower than the headline number, because some energy is lost as heat during charging. That is normal.

Watts: how fast it charges

Capacity is only half the story. Output power, measured in watts (W), decides how quickly your devices charge.

  • 20-30W fast-charges most phones.
  • 45-65W can charge many tablets and smaller USB-C laptops.
  • 100W and above is what you need for larger laptops such as 14-16 inch models that charge over USB-C.

Check your laptop's original charger: if it is rated 65W, choose a power bank that can output at least 65W from a single USB-C port.

Ports and built-in cables

USB-C ports with Power Delivery (PD) are the most useful today, because they fast-charge phones, tablets and laptops. Some power banks also have built-in cables, which means one less thing to forget at home.

Smart displays

Premium power banks show the exact battery percentage and the live charging wattage on a small screen. It is a simple way to confirm you are really getting fast charging.

Our quick recommendations

  • Everyday phone use: a 10,000-20,000mAh power bank with a USB-C fast-charging port.
  • Phone plus laptop: 20,000mAh or more, with at least 65W USB-C output.
  • Heavy users and travellers: 24,000-25,000mAh with 140W or more and a smart display.

Also check airline rules before flying: power banks must go in your hand luggage, and most airlines limit capacity to around 100Wh (roughly 27,000mAh) without special approval.

Browse our range of original Anker power banks - every one comes with Fulrix's 12-month warranty and delivery across Nigeria. Need help choosing? Send us a message on WhatsApp.

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