How to choose a power bank for blackouts and long commutes

A dead phone in Nairobi is more than an inconvenience. It can mean no M-Pesa, no ride-hailing, no maps and no way to reach family. A good power bank keeps you connected through power cuts, long commutes and travel upcountry. Here is how to choose one that fits.

Understand capacity (mAh)

Power bank capacity is measured in milliamp-hours (mAh). Real-world output is lower than the number on the label because some energy is lost during charging, so expect roughly two-thirds of the stated capacity to reach your phone.

As a rough guide for a phone with a 5,000mAh battery:

• 10,000mAh: about one to two full charges. Light and pocketable, ideal for daily commuting.
• 20,000mAh: about three to four charges. Good for blackouts, travel or charging two devices.
• 30,000mAh and above: for long trips or households sharing one power bank. Heavier to carry.

Check charging speed

Charging speed is shown in watts (W). Look for:

• Fast charging support that matches your phone, such as USB Power Delivery (PD) or Quick Charge.
• Output of 18W or more for faster phone top-ups.
• Higher output (45W to 65W and above) if you want to charge some laptops via USB-C. Check your laptop supports USB-C charging first.

Also check the input speed. A power bank that recharges quickly is handy when electricity returns for only a short time.

Ports and cables

• USB-C is now standard on most Android phones and newer iPhones, and often works both in and out.
• USB-A is useful for older cables and devices.
• Two or more outputs let you charge a phone and earphones at once.

Some power banks have built-in cables, which saves you hunting for one in your bag.

Size and weight

Think about where it will live. A slim 10,000mAh model fits a pocket or small handbag. A 20,000mAh bank belongs in a backpack. If you fly, airlines limit power bank capacity in carry-on luggage, so check your airline's rules before travel.

Safety tips

Cheap, poorly made power banks can overheat. To charge safely:

1. Buy from a seller you trust and avoid unbranded units with no clear specifications.
2. Do not charge it under pillows or blankets, where heat cannot escape.
3. Stop using any power bank that swells, gets very hot or smells unusual.
4. Keep it away from water and direct sun, such as a car dashboard.
5. Use a good-quality cable, as damaged cables can cause problems too.

Making it last

Top it up regularly rather than storing it empty for months. If you keep one for emergencies, charge it every few weeks so it is ready when the lights go out.

Which one suits you?

• Students and commuters: 10,000mAh with fast charging.
• Families during power cuts: 20,000mAh with two or more ports.
• Small-business owners and travellers: 20,000mAh or more with USB-C PD, possibly laptop-capable.

Find the right capacity in our power banks, and pair it with a reliable charger or cable so you are ready for the next blackout.