How to choose Power Bank (external battery)
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An external battery is several batteries of a certain capacity, enclosed in a case with an outlet for charging gadgets. Among the case materials, plastic predominates, less often metal, but there are also steel Power Banks.
Battery type
Power Bank batteries are built on the basis of one of two technologies that are found on the market in approximately the same proportions:
1) Li-Ion (lithium-ion batteries) - have a good "capacity-dimensions" ratio and are practically not affected by the "memory effect" (it is present, but does not adversely affect the battery charging process);
2) Li-Pol (lithium polymer batteries) - an improved version of Li-Ion batteries, which is even more compact in size with a similar capacity and the complete absence of the "memory effect"; at the same time, this type is more sensitive to cold.
Performance indicators
Capacity
This indicator acts as a key parameter when choosing an external battery. The dimensions of the device, its weight and, accordingly, the cost directly depend on the capacity. And most importantly, it affects the number of charge cycles for third-party gadgets.
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Power Bank with a battery capacity of up to 5000 mAh is suitable for double charging a smartphone with a battery of about 2000 mAh |
So, a Power Bank with a battery capacity of up to 5000 mAh is suitable for double charging a smartphone with a battery of about 2000 mAh (for example, Assistant AS-4411). More voluminous external batteries will fit for repeated recharging of phones with a built-in high-capacity battery or for tablets, in which the batteries are a priori larger.
There are also giant models on the market with a claimed capacity level of 50,000 mAh (Power Plant K2, Drobak Lithium Polymer Battery 50,000). But in reality, these figures are not true.
There are actually several reasons for the discrepancy between the claimed capacity. The simplest of them is an attempt to deceive customers by a negligent manufacturer. These are found on Chinese Internet resources. Therefore, it is much safer to deal with official stores that are responsible for the products sold.
Another common reason for the discrepancy is the difference between the voltage on the batteries of the external battery (often on the order of 3.7 V) and the standard voltage of the USB bus (5 V). The need to convert the voltage to the desired value during the operation of the Power Bank is accompanied by capacity losses. They can reach 25-35% of the claimed figure. For example, the effective capacity of an external battery Xiaomi Mi Power Bank 16000 will be a little less than 11000 mAh.
When choosing a Power Bank, first of all, you need to start from your own needs. So, those who like to surf the Internet or surf social networks should better turn their attention to models with a capacity of up to 10,000 mAh, and mobile gamers and video streamers should look at more capacious batteries(because these operations consume battery power more actively). The main thing is that the Power Bank does not interfere with its owner and is conveniently located among his everyday gadgets and accessories.
Charging current
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The value of the second important indicator affects the charging speed of gadgets. |
The value of the second important indicator affects the charging speed of gadgets. There are varieties of Power Banks with a maximum output current through the USB port at ≤1A, 1.5A, 2A and ≥3A.
When choosing an external battery, pay attention to the charger of those gadgets that you plan to recharge with it. Usually it indicates the required charging current. Among the smartphone family, its value prevails at the level of 1 A, tablets will ask for 2 A already. A number of Power Bank models have several USB ports, each of which can offer a different level of output current. But more on that below.
Needs are different
As mentioned above, the dimensions and weight of an external battery depend on its capacity. And the next link in the chain is the form factor of the device. Rectangular Power Banks have won the greatest popularity. But for different needs, other versions are also available. For example, the battery Mophie Portable Battery Power 2nd Gen will suit connoisseurs of saving space - it pretends to be a keychain and is included in the category of compact models of external batteries. Such assistants cannot boast of outstanding capacity indicators, but they will not burden their owner with excess weight and will always be near him. Yes, they will not allow you to fill the tanks of any gadget completely, but they completely cope with their main purpose - the ability to stay in touch or urgently make a call using a mobile phone with a dead battery.
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Batteries with a large capacity on board often have in their an arsenal of two or three USB ports for charging gadgets. |
External batteries can also help keep your action camera or camera running. In these cases, the choice is made according to standard criteria - based on the battery capacity and the magnitude of the charging current. Regular batteries for photo and video equipment do not require exorbitant capacity, so a 5000 mAh Power Bank is usually enough to recharge them.
Batteries with a large capacity on board often have two or three USB ports for charging gadgets. Usually, in this case, one output produces a large charging current (2 A), and the rest are low-power (1 A). Also, such models allow you to charge several devices at the same time (which will undoubtedly please your friends, for example, when gathering in a cafe).
Additional "chips" and interesting features
Charging adapters. The vast majority of Power Banks are equipped with a USB outlet for charging gadgets. You can connect a cable with a connector for any type of device (microUSB, Lighthing, etc.) to it. But there are models with a built-in wire that hides in the body of the device. Some of them are designed to charge gadgets via a microUSB port (Samsung EB-PG850, Genius ECO-u306), while others are tailored specifically for Apple technology (Techlink Recharge Ultrathin 3000 Lighthing, Macaly MBP26L).
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The remaining charge level of the external battery is often displayed with coloured LEDs |
Charge indicators. The remaining charge level of an external battery is often displayed using coloured LEDs located on the device case (usually there are 4 of them). Advanced Power Bank models have a separate screen that displays the remaining battery percentage (Power Plant PB-LA603, Powertraveller Minigorilla, etc.).
Flashlight. Many models have an LED flashlight in their equipment. Due to low power consumption, the flashlight can work for a long period of time.
Impact resistance. The case of models with shock protection is made of durable materials. Its main function lies in ensuring the integrity of the device during falls (becomes relevant when doing active sports and recreation).
Charging laptops + mode switch. Particularly powerful Power Banks have the function of charging laptops. And since the power supply voltage of portable computers varies depending on the model of the device, it will not be out of place to pay attention to external batteries with a voltage switch. Manufacturers of such batteries often supplement their offspring with a whole range of various cables and adapters for any type of device, offering the consumer connectors for connecting to a mobile phone and various types of power plugs for laptops. One of these batteries is Extra Digital MP-S23000 .
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The battery case limits the scope exclusively by smartphone. |
Battery case. The form factor of the cover limits the scope of the external battery to a compatible smartphone only. Nevertheless, some find it attractive, because in this case, the Power Bank does not require a separate place to carry it.
Solar panels. A small caste of batteries with a built-in solar panel is theoretically capable of renewing its own energy supply under the influence of sunlight (or other bright light source). In fact, one should not attach great importance to this function, because The energy generated by the solar battery can only compensate for the self-discharge of an external battery.
Removable batteries. Removable batteries are even rarer. Various batteries can play their role: AA type (for example, the Goal Zero Guide 10 Plus Adventure Kit requires 4 AA batteries for its operation), type D (the Coleman Energy Pack portable charger works on such batteries), etc.
Support fast charging technology. Significantly speed up the process of charging gadgets will help Power Bank'i with support for Qualcomm Quick Charge 2.0 technology. It should be noted here that external batteries that support fast charging solely for their own needs can be labeled in this way (such as, for example, Xiaomi Mi Power Bank 20000).
Good luck with your choice!
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