A guide for those who are tired of being without the Internet and communication at the most inopportune moment.
Every year there are new smartphones, more powerful and voracious. But mobile batteries are not developing as fast as we would like. That’s why you can use a power bank, a compact external battery that recharges your phone in the absence of sockets.
Unlike the same smartphones and other varieties of advanced technology, portable power sources can not boast a special variety. And it makes perfect sense. But there’s something you need to know about them.
Capacity and accompanying dimensions
The most important parameter of the external battery is its capacity, which the manufacturer usually indicates in milliampere-hours (mAh). Roughly speaking, this is the amount of energy that the power bank can store (but not transmit).
Please note that due to the fundamental laws of physics, no external battery can transmit 100% of the stored energy, and no smartphone can fully absorb the energy it receives. Part of the resource is always lost when the voltage is converted, and a certain amount goes into heat.
On average, cumulative losses range from 30 to 40%, although individual (and usually more expensive) models of external batteries and smartphones can boast an efficiency of about 90%.
In other words, the power bank with a stated capacity of 10,000 mAh in practice will transfer about 7,500 real MAh, that is, fully charge the smartphone with a battery capacity of 2,500 mAh⋅h, not four times, but only three.
Keep in mind, however, that this calculation is very average. You can only check the real losses when recharging a particular smartphone from a specific external battery.
But chasing the maximum capacity is not worth it. The higher it is, the more expensive, heavier, and bigger the power bank – keep that in mind. If you’re going to charge just one smartphone, you’ll likely have enough external battery for 10,000 mAh. But if you plan to support a power bank several phones or a laptop or tablet, it is better to choose a device for 20,000-30⋅000 mAh.
Inseparables and cables
Many external batteries, especially low-cost models, are sold wirelessly. You’re supposed to use a USB cable that comes with a smartphone to connect. In this case, ensure that the end of this wire (most often a USB-A port or USB-C) coincides with the type of output connector on the power bank.
Some external batteries are sold with the plug-in or even built-in cables. In this case, it is important to make sure that its end (most often, it is a port of micro-USB, Lightning, or USB-C) is suitable for your smartphone. If there are problems with port incompatibility, they can be solved by buying a suitable cable or adapter.
In addition to the type of corrosion on the power bank, pay attention to their number.
For example, if you’re going to charge two devices simultaneously, look for an external battery with two power ports.
In addition, the power banks have an input – to charge the outermost battery from the computer or power grid. Usually, it is a micro USB, and the corresponding cable comes in the set. Don’t confuse this with weekend ports.
The output of the current of the external battery
The speed of charging the smartphone will depend on many parameters of the power bank, but the determining factor is the output power of the current. It should be no less than that provided by the manufacturer of the smartphone.
Learning the optimal power of current for your smartphone is easy. Take a fork that came complete with the device and see the output value. It’s going to say something like 5 V – 2 A. It would help if you had a figure standing next to A because the power of current is measured in amps.
You can find out the power bank’s output on the manufacturer’s website or in the instructions. If the external battery has more than one output, the current force is sometimes indicated directly on the body next to each port.
If you have two or more eroding, you should remember that the total output of the power bank current is limited.
For example, the battery may have two outputs of 2.5 A each but give out a total of no more than 4 A. Accordingly, when connecting two devices at once, each of them will be able to receive no more than 2 A.
If the output of the current of the external battery is less than that on which the smartphone is designed (for example, 1 A at the power bank and 1.5 A at the smartphone), the charging will still occur, but noticeably slower.
There is no need to be afraid of the output of the external battery current than for which the mobile device is designed (e.g., 2 A at power bank and 1 A at the smartphone). Mobile devices have built-in protections that limit the incoming current to an acceptable value. Simply put, your smartphone won’t explode or melt.
For the same reason, the mobile device will not charge faster if you use a plug or power bank with output power above the manufacturer.
Fast charging support
Let’s say you find an external battery with the right output power, but the complete plug still charges the smartphone faster. What’s going on? Most likely, your smartphone supports some speed-charging technology like the quick Charge 3.0, the quick Charge 4.0, or the option with its own name from a particular manufacturer (e.g., mCharge from Meizu). Look for a power bank that is friendly with the fast charging technology used in your smartphone.
External battery current input
No matter how heavy the external battery you buy, its own energy supply will sooner or later be exhausted. It’s nice when the power bank quickly charges the Bluetooth Earphone, smartphone, but even more pleasant if it charges quickly.
The speed of the charging power bank is determined by its input power, voltage, and the presence of a particular technology that provides a more rapid replenishment of its own charge. Now there are external batteries that are fully charged in less than 30 minutes.
Please note that the power bank’s own charging speed does not affect the speed at which it charges the smartphone.
But a lack of understanding of technology and gaps in English knowledge can mislead the user. For example, you see a power bank that says something like a 5-minute charge. You’d think this miracle device charges your smartphone in 5 minutes, but it’s actually different.
Let’s say the capacity of a particular battery is 10,000 mA⋅hand. It is fully charged in 20 minutes. In this case, in 5 minutes, it will fill up about 2,500 mAh. And this charge is really enough to charge a typical smartphone.
The problem is that the charging time of the smartphone is limited by its own maximum input power of the current and the presence of support for this or that fast charging technology.
Simply put, the pathetic phrase 5 minutes charge actually means: “This power bank needs 5 minutes to get the charge needed to further fully charge the smartphone.” Don’t get caught in marketing noodles and pump your technical literacy.
Type of external battery
Depending on the batteries used, lithium and lithium polymer batteries are distinguished. The latter is considered more stable and compact. But the difference is not so significant as to focus on it. So you can choose any of these types.
There are a few more nuances that are useful to pay attention to when choosing a power bank.
- The material of the case. Plastic batteries are cheaper and lighter than metal. Remember that.
- The presence of an indicator. Some power banks display the remaining charge level on a small built-in display, which is very convenient.
- Wireless charging. If your smartphone and power bank support common wireless charging technology, you can connect them without cable.
- The presence of a solar panel. If there is a built-in solar plate on the battery body, it will be able to charge in clear weather.
- Protection from external influences. Portable batteries can be protected from moisture, shocks, and dust. If you lead an active lifestyle, such properties can be useful.