Every smartphone owner has thought about buying a power bank. Considering how much smartphones give us and how quickly they are discharged, the appearance of this desire is quite natural. But before you buy an external battery that you like, you should still understand the positive nature of its influence. There are a lot of rumors around the Power Bank, including negative ones, so let’s figure out exactly how a portable device affects the battery.

1. Access to energy to charge anywhere

Regardless of whether you are a few steps away from an outlet or flying in an airplane, an external battery gives you the ability to keep your device’s battery charge at the right level. You will no longer have to worry about having a dead phone again, especially in emergency situations.

2. Mobility

These devices are specially designed for easy movement. This means that they are usually light and thin, which simplifies their placement in bags, pockets and transportation itself in general.

3. Universal charging

Many portable chargers that are on the market are designed to charge various types of devices. This is an ideal option for people who own more than one type of electronics or their different brands, for example, if you have an iPhone and a Samsung tablet at your disposal, you can easily charge two different devices using different ports and even do it at the same time. In this case, you need to check which ports are provided in the design before buying.

Disadvantages of owning a Power Bank

1. Long and inconvenient charging of the batteries themselves

Unfortunately, charging your Power Bank is less convenient than charging other devices. Most devices have a USB input and require a special wire and a block. On average, it may take up to 15 hours to fully charge the battery. Some cheap models do not have light indicators reflecting the charge level, and you cannot know exactly how long your Power Bank has left to charge.

2. The relevance of buying an additional battery is not always high

If you do not use your phone too actively or do not travel often, then buying a Power Bank may well be far from a priority and may not be necessary at all. There is no need to spend extra money on one of these devices just for convenience.

As for the negative impact of an external battery on the battery of your phone, we can safely say that this is a myth. Modern technologies allow devices not to overload the battery after it is fully charged. There is a list of general recommendations regarding smartphone charging, and if you stick to them, your smartphone will keep charging for as long as possible, and the
battery will not need to be replaced soon.

What capacity should I choose? Difficult math

Imagine that you have a smartphone with a 5,000 mAh battery. What capacity should the power bank have so that it can charge your battery twice? It would seem like 10,000 mAh.

But no.

The vast majority of external batteries use 18650 lithium-ion batteries with an output voltage of 3.7 V. And the standard voltage with which power banks charge your devices is 5 V. And most often manufacturers indicate the battery capacity for 3.7 V, and to get the value for 5 V, you need to multiply the capacity by 0.74. That is, at a voltage of 5 V, a real 10,000 mAh will be able to give a model that has (conditionally) 13,500 mAh in characteristics.

In addition, we must not forget about efficiency and self-discharge. All 100% of the capacity of the power bank will not get into your smartphone, because part of the transmitted energy is converted into heat. And if the battery is left in the bag for a week, then during inactivity it will lose part of the charge.

So the stock needs to be laid at least with a factor of 1.5. Do you want to fully charge the 5,000 mAh battery 2 times? Take a 15,000 mAh power bank.

There is a nuance: the average 10,000 mAh power bank weighs about 200-250 g. 20,000 mAh is already almost half a kilo. It’s quite normal for fishing and traveling, but it’s better to find an easier option for every day.

Is it possible to charge a laptop?

Thanks to the USB-C port and the Power Delivery protocol, modern power banks deliver up to 100 watts of power. For comparison: A 16-inch MacBook Pro with a powerful processor and discrete graphics is charged using a 96W power adapter. You won’t notice a difference between an outlet and a power bank.

But there are two nuances:

● Your laptop and power bank must support the Power Delivery protocol. The presence of USB-C does not guarantee it.

● The output power of the USB-C port of the external battery should not be less than the power of the charger of your laptop.

If you don’t want to guess with power, the option with the maximum for Power Delivery of 100 watts is suitable for most laptops.

So, a simple checklist:

1. Choose a container with a margin of 1.5 times.
2. It is better to take a 5,000-10,000 mAh model for every day, it will be difficult to carry more capacious ones with you.
3. Look at the power, and if it is not specified — at the current and voltage.
4. If the power bank and your devices are charged through the same connector, you do not have to carry an extra cable with you.
5. You don’t need wireless or fast charging if your smartphone doesn’t support them.
6. To charge a laptop, both the power bank and the laptop must support Power Delivery, and the output power of the external battery should not be lower than the power of the main charging.