Swollen Powerbanks - Causes, Prevention and What To Do

Swollen powerbanks

This article explains why powerbanks can swell, how to lower the risk, and how to look after them day to day. It applies to common sizes like 5,000mAh, 10,000mAh, 20,000mAh, 27,000mAh and 30,000mAh.

What does it mean when a powerbank swells?

Swelling means the battery inside has started to break down. The case may look puffed up, split, or feel tight. This is a safety issue. A swollen powerbank should not be used.

Why do powerbanks swell?

The battery inside most powerbanks is a lithium battery. Over time, a few things can cause gas to build up inside the battery, which makes it swell.

Common causes include:

• Heat
  Leaving the powerbank in a hot car, near a window, or next to heaters.

• Overcharging or poor charging habits
  Using cheap chargers, damaged cables, or leaving it plugged in all the time.

• Heavy use while charging
  Charging the powerbank while also powering devices for long periods.

• Age and wear
  Batteries slowly wear out after many charge cycles.

• Physical damage
  Drops, crushing, or bending can damage the battery inside.

Larger powerbanks hold more energy, so when they fail, swelling can be more noticeable.

How can I avoid swelling?

You cannot stop battery ageing completely, but you can lower the risk.

• Keep the powerbank cool and dry

• Do not leave it in cars, especially in summer

• Use good quality chargers and cables

• Unplug it once it is fully charged

• Avoid charging and discharging at the same time for long periods

• Do not store it fully flat or fully full for months
  Around 40 to 60 percent is best for storage

Best ways to use a powerbank

• Charge your device, then unplug when done

• Let the powerbank cool down after heavy use

• Charge it on a flat, hard surface

• Do not cover it while charging

• Check it now and then for changes in shape or heat

How to care for your powerbank long term

• Use it at least once every few months

• Store it away from heat and direct sun

• Keep it away from water and moisture

• Stop using it if it feels unusually hot, smells odd, or looks swollen

What should I do if my powerbank swells?

• Stop using it straight away

• Do not try to squeeze, puncture, or open it

• Keep it away from flammable items

• Take it to an approved battery recycling or e-waste centre
  Do not put it in household rubbish

If the powerbank is under warranty, contact the seller or manufacturer for advice.

Final tip

Powerbanks are safe when used properly, but they are still batteries. Treat them with care, keep them cool, and replace them when they show signs of wear. If something does not look right, it is always safer to stop using it.