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How-to Guide

How-to Guide

Do’s and Don’ts when using Power Banks

What is a Power Bank?


A Power Bank is a portable charger designed to recharge your electronic devices when you’re on the move. Ranging in size from slim, pocket-sized devices up to larger, higher-capacity Power Banks – they can be used to charge smartphones, tablets, earphones, smartwatches and other mobile devices.

What is the right capacity for me?

 
The capacity stored in your Power Bank is never the exact capacity that reaches your device effectively. To easily calculate how often your device can approx. be charged with one full charge of a certain Power Bank you can use this rule of thumb:

How often can I charge my device with the Power Bank?

Capacity Power Bank (mAh) ÷ Accu Capacity Device × Impact Factor 0.7

With a Power Bank of the mid-price segment with 15.000 mAh you can charge a Samsung Galaxy S10 approx. 3 times.

15.000 mAh ÷ 3.400 mAh x 0.7
= 3 Charges*


*Based on internal VARTA Tests.
Accu capacity based on Samsung Galaxy S10 battery specifications at samsung.com. Performance may vary depending on device.

The number can vary due to different influencing factors:

  • The accu of your device is not completely discharged
    (best case ~ 20 %).
  • You never completely charge your device
    (best case ~ 80 %).
  • The capacity of the Power Bank (and your device) slightly decreases over time due to the Lithium-Ion accu.
  • If you use your device during the charging process the provided power is being consumed simultaneously.

Did you know?

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It is not allowed to carry Power Banks which use Lithium-Ion batteries in your checked-in luggage. They need to be stored in your carry-on baggage only and should not exceed 100 Wh*.

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There is no need to fully charge and discharge (full cycle) your Power Bank. It is possible to add 10 %, 20 % or 30 % anytime you want. Partial cycles can even prolong the lifetime of your Lithium-Ion battery.

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On average, a Power Bank can be cycled 300 times. Using the stated Tips & Tricks you can prolong your Power Bank’s life significantly!

*As there are no clear rules, most Airlines follow the IATA guidelines.
Wh = watt hours is the measure for electrical energy that is stored in the Power Bank.

How to extend your Power Bank’s life

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DO consider temperatures

The Power Bank should not be charged at temperatures of under 5 degrees and should not be discharged at temperatures over 40 degrees.

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DO NOT drop the Power Bank

The Power Bank contains a circuit board and other fragile components inside. Always make sure to handle it carefully. Don't drop or throw it.

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DO disconnect the charger of your Power Bank as soon as it’s fully charged

This is also useful when charging your device.

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DO NOT expose the Power Bank to extreme temperatures

Batteries prefer temperatures between 5 and 25 degrees. The more you deviate from that comfort zone, the bigger are the irretrievable capacity losses that might result. This also includes not covering the Power Bank with a blanket or clothes.

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DO charge your Power Bank even if you don’t use it

To keep the Power Bank in good working condition, you should charge it at least every three months.

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DO NOT keep your Power Bank in pocket or bag with metal objects

It is always best to be careful and make sure they are never placed in a position where metal objects could short the output.

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DO avoid to fully charge your Power Bank

For best performance and longer lifetime do charge your Power Bank only up to 80 % and discharge only up to 20 %. Most Power Banks have a charging status indication.

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DO NOT charge your Power Bank and your device at the same time

It affects the battery health of Power Banks due to excessive heat production in both kinds of charging.