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Are power banks bad for your phone? Can they damage the battery?

Are power banks bad for your phone? Can they damage the battery?

Under normal circumstances charging a phone with a power bank will not damage the battery. In fact, it should have the same effect as charging your phone via its conventional charger.

For the phone, it does not matter which power source you use as long as the current is within the admissible limits. You can even charge the phone directly via solar panels as long as the power is stable and has the right values. Smartphones require a 5V input to get charged. So as long as the device you’re charging them with delivers that output, you don’t need to worry.

Power banks deliver at least 5V of power, but in some cases, they can deliver more than 5V too. For example, some power bank models can deliver up to 20V if needed as in the case of charging laptops. But even if the power bank can deliver more than 5V of power, you still shouldn’t worry as both the power bank and the phone have power regulating circuits, that allow the mobile to only take 5V and not more. However, should the charging regulating circuit fail, then you could indeed see a negative impact on the phone’s battery.

Think of the power bank as a tank or reservoir from which the smartphone can draw power. The power reservoir cannot forcefully feed power to the phone. Thus you need not worry that power banks damage your battery.


Although the chances of a power bank damaging the battery of your phone are highly slim, you can still take some precautions in order to avoid any possible accidents.

First of all, make sure you get a high-quality power bank from a reputable brand. Avoid buying cheap, knockoff power banks off of eBay or Aliexpress. Although they might look like a great deal at first, they’re generally very low-quality devices and you never know how your phone would react to them. We warned about this aspect in our previous article in which we discussed the topic of 100000mAh power banks.

Similarly, make sure to use a high-quality charging cable. If your power bank is from a good brand and comes with a charging cable, use that one. Alternatively, use the charging cable that came with your phone. Avoid using cheap cables that you buy for less than $1 from street vendors or other questionable sources. They can have negative effects on your devices during the charging process.

Other things to keep in mind:

  • If possible try to unplug your phone once the charge has reached 100%. You can even do so anywhere between 80% and 100%
  • Try not to let your phone discharge until 0%. Ideally, you’d recharge it as soon as it hits 20% or lower
  • Check the voltage required by your phone and the voltage that can be supplied by your power bank and make sure they match
  • Do not use the power bank if you notice any type of physical damage: bent, bloated, smoke coming out, etc. Damaged power banks can spoil your phone’s battery, rendering it unusable, and they can even explode.
  • Make sure you have a matching charging cable. Most power banks come with USB/micro USB or USB/USB type C charging cables, but some phones such as the iPhone, for example, require a different charging port (Lightning in this case).
Conclusion. Are power banks bad for your phone?
You should not worry that using a power bank can damage your phone battery. The chances of that happening are very slim. Just make sure you use a power bank from a reputable brand and you should be fine.

In case you’re not yet sure which power bank to get, check out our curated list of best portable chargers.

You can also check out our power bank review database. You can use the custom filter in order to quickly find the power bank with the features that interest you the most.

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