Battery capacity
The higher the battery capacity, the more energy the power bank is able to accumulate and then transfer when charging to gadgets connected to it. But it should be borne in mind that not all of the accumulated energy goes specifically to charging – part of it is spent on service functions and inevitable losses in the process of transmission. So in the specifications, the real capacity of the power bank is also often specified. If there is no data on real capacity, then when calculating it is worth proceeding from the fact that it is usually somewhere 1.6 times lower than the nominal one. For example, for a model with a nominal capacity of 10,000 mAh, the actual value will be approximately 6300 mAh.
As for the specific values of the nominal capacity, then in models with the lowest performance it is
5000 – 7000 mAh and even
less ; such power banks are suitable as a backup source of energy for 1 – 2 smartphone charging with a not very capacious battery or other similar gadget. The
10,000 mAh solutions are the most popular nowadays – in many cases, this option provides the best price-capacity ratio. The
20,000 mAh and
30,000 mAh options are also very common. But even a capacity of
40,000 mAh or
more, thanks to the development of modern
...technology, is quite common.Bundled cables (adapters)
Types of cables and/or adapters for charging external devices included in the power bank set.
The type of such cables is indicated by the plug used to connect to the gadget being charged; connection with the power bank itself is usually carried out through a standard USB A or USB type C output. We emphasize that in this case, we are talking about detachable cables/adapters; types of built-in charging cables are specified separately (if any — see below).
In general, this parameter allows you to evaluate the possibilities of a power bank available out of the box, without purchasing additional accessories. As for specific interfaces, most often external batteries nowadays are equipped with
microUSB,
USB type C and/or
Lightning cables/adapters; more specific connectors are extremely rare. Here are the features of the most popular options:
— microUSB. A connector that is extremely common in modern portable gadgets. It is inferior to the newer USB type-C in terms of convenience and several performance specs, but still has not lost popularity.
— USB type C. A relatively new standard for miniature USB connectors, used for charging both portable equipment and larger devices — in particular, some ultra-compact laptops. Physically, it differs from microUSB in a slightly larger size and a two-sided design that allows you to connect the plug b
...oth ways. In terms of performance, USB type C is notable for better compatibility with fast charging technologies (see above): more fast charging technologies can be used with it, and Power Delivery was created based on this connector. At the same time, the presence of a USB type C cable does not mean support for fast charging.
— Lightning. Standard original connector for Apple gadgets; other manufacturers do not have such a port.
Note that if several types of bundled cables/adapters are claimed in the specs, the specific format of such accessories may be different. For example, "microUSB plus USB type C" could mean two separate cables, one cable with two plugs, a cable with one plug plus an adapter to another, etc.Built-in charging cable
Type of
built-in cable(or cables) for charging external devices, provided in the design of the power bank.
The main advantage of such equipment over a removable one (see "Bundled wires (adapters)") is that the built-in cable is always in place — you can lose it only together with the power bank itself (or as a result of an "accident" with physical damage to the structure) . On the other hand, such a cable cannot be quickly replaced with another one (longer, with a different plug, etc.); and if it is damaged, you will have to carry the power bank for repair or change it entirely. As for the type of built-in wires, this is indicated by the type of plugs for charging external gadgets that such wires are equipped with. Most often these are
microUSB,
USB type C and/or
Lightning connectors, here is a more detailed description of them:
— microUSB. Relatively old, but still popular connector for portable equipment (mobile phones, tablets, players, etc.); used by almost all manufacturers of such equipment, except for Apple with their proprietary Lightning interface (see below).
— USB type C. A miniature connector, released relatively recently, but gaining more and more popularity (to the point that even Apple, which usually prefers proprietary interfaces, uses USB type C to charge its laptops). It is small (slightly l
...arger than microUSB) and has conveniently reversible design, well optimized for various advanced features, including some fast charging technologies (although the presence of USB type C does not mean support for such charging).
— Lightning. Apple proprietary connector used in portable devices of this brand (iPhone, iPad, iPod); does not apply to other manufacturers. Note that for a power bank with such a cable, MFi certification is desirable (see above).
If there are several types of plugs, they can be provided both on individual wires and on one combined cable. But if a removable adapter is included in the kit, its type is indicated in the “Bundled wires (adapters)” paragraph.