Size
The battery sizes that the charger is compatible with. In this case, the adapters supplied in the kit (see below) are not taken into account in this paragraph, we are talking only about the memory as such.
The standard dimensions describes the shape, dimensions, connector design and operating voltage of the battery; thus, it is one of the most important parameters for determining compatibility with a particular charger.
The most popular sizes for which modern “chargers” are made can be divided into 1.5-volt (marked in Latin letters
AA,
AAA,
C,
D) and 3.7-volt (have digital markings
14500,
17500,
18650,
22650,
26650, etc. .P.). More about them:
— AAAA. The smallest version of the "finger" dimensions: batteries of the same cylindrical shape as the well-known AA and AAA, but with a size of only about 8 mm and a length of about 43 mm. Similar in application to AAA, but very poorly distributed.
— AAA. Size, colloquially known as "mini finger" or "little finger batteries": cylindrical batteries with a size of 10.5 mm and a length of 44.5 mm. They are mainly used in miniature devices for which there are not enough “tablet” bat
...teries, and larger elements are too bulky.
— AA. Classic "finger" batteries with a size of 14 mm and a length of 50 mm, one of the most popular modern standard sizes (if not the most popular). They are used in a wide variety of types and price categories of devices, including even external battery packs for SLR cameras.
- C. Batteries in the form of a characteristic "barrel". They are similar in height to finger-type AAs, but almost twice as thick - 50 mm and 26 mm, respectively - due to which they have a higher capacity.
- D. The largest dimensions of consumer grade 1.5V batteries, 34mm in size and 61mm in length. It is mainly used in high-power flashlights and devices with high energy consumption.
3.7-V batteries are indicated by a five-digit number. In it, the first two digits indicate the size (in millimeters), the remaining three indicate the length (in tenths of a millimeter). For example, the popular dimensions 18650 corresponds to a battery with a size of 18 mm and a length of 65.0 mm. It is worth noting here that there are 3.7-volt cells that are the same dimensions as the 1.5-volt ones described above (for example, the 14500 dimensions is similar to AA finger-type), but both types are not interchangeable due to the difference in voltage.
A separate category is 9-volt R22 batteries, also known as PP3: these are rectangular elements in which a pair of contacts is located on one of the ends.Max. charge current
The highest current that the device can provide when charging the battery (or the nominal value of the charging current, if it is not adjustable).
Charging current is one of the most important parameters for any charger: it determines the speed of the process and compatibility with certain batteries. In general, the higher the current, the faster the process, the less time it takes to charge. At the same time, some batteries may have recommendations for the optimal current strength and restrictions on its maximum values. Therefore, mindlessly chasing a powerful charger is not worth it: at first it's ok to clarify how justified such power will be.
Note that in multi-channel devices (see "Independent channels"), the maximum current strength can be achieved when only part of the channels are operating. The indicators provided when all channels are operating simultaneously are indicated separately for such models (see "Charge current (all channels)").
Number of settings
The number of separate charge current settings (see above) provided in the design of the charger. For example, a device with 4 settings may provide options for 200, 400, 800 and 1000 mAh. In general, the larger this number, the more accurately you can choose the charging current for a particular situation.
Min. discharge current
The smallest current that the device is capable of providing in battery discharge mode.
Some specific functions are based on the discharge of the battery installed in the charger (see below for more details); in this case, it often becomes necessary to set a certain value of current strength, which is optimal for a given battery. The lower the minimum discharge current (with the same maximum) — the wider the adjustment range and the higher the probability that the device will be able to provide the optimal discharge mode.
Max. discharge current
The highest current that the device can provide in battery discharge mode.
Some specific functions are based on the discharge of the battery installed in the charger (see below for more details). The higher the maximum value of the discharge current, the less time it takes to “drain” energy from the battery. On the other hand, for some types of batteries and discharge modes, specific current recommendations may be provided, and exceeding them can be fraught with overload, overheating, and even fire. Therefore, it is necessary to specifically pursue high values of the discharge current only if it is justified from a technical point of view.
Preliminary discharge
Pre-discharge is useful for batteries that are prone to memory effect - they need to be charged only after the charge is completely depleted. In accordance with the name, a charger with this function is capable, if necessary, of discharging the installed battery “to zero” before starting charging. At the same time, some models are able to automatically detect the presence of residual energy and turn on a preliminary discharge, in others it must be turned on manually.
USB charging power
The ability for the charger to receive power from a standard USB port (and, accordingly, charge batteries from this port).
USB connectors are extremely widespread in modern electronics, both in stationary equipment like PCs and in portable ones like laptops or tablets. Due to this, such power can be useful both at home or in the office, and in the absence of outlets nearby. And in general, this function greatly expands the possibilities of connecting the memory. True, you need to take into account that
USB ports differ in the power of the supplied power, and some models may be with weak USB charging. And also there are chargers with a round DC port, for which only the native cable is suitable.
Mains plug on cable
Chargers with a plug for connecting to a socket on the tip of the mains cable. Models
with a plug on the wire provide freedom of placement of the “charger” (especially in cramped free space near the outlet). So that the cable does not get tangled at hand, in many models it is made removable, which makes it easy to store the charger.