The technology by which the battery or accumulator is made.
The technology determines the chemical composition of the “filling” and the characteristics of the reactions occurring in it; as a result, both general performance characteristics and specific rules of operation and storage directly depend on this parameter. Among rechargeable batteries in our time, the most popular technologies are
Li-Ion,
LiFePO4 and
Ni-Mh,
Ni-Cd and Ni-Zn are noticeably less common. There is more variety in batteries. Thus, inexpensive full-size elements are made
of salt ;
alkaline (alkaline) technology in one form or another is used in advanced full-size and relatively simple miniature 1.5 V coin batteries;
silver oxide elements are a more advanced (and expensive) analogue of alkaline “tablets”; and
lithium technology makes it possible to create miniature power supplies with a voltage of 3 V. More rare and specific cases are the Li-SOCl2 technology, used in full-size batteries with increased reliability requirements, as well as the zinc-air operating principle used in specialized power supplies for hearing aids. Here is a more detailed description of each of the options mentioned:
— Li-Ion. Lithium-ion is
...one of the most popular battery technologies today; originally created for portable equipment, but later began to be used everywhere. Such batteries have excellent charge density - that is, a solid capacity with a relatively small size and weight. In addition, they charge quickly, and the “memory effect” (characteristic, in particular, of the Ni-Cd cells described below) is practically absent in such energy sources (more precisely, it is compensated for by built-in charge controllers). Among the disadvantages, one can note a slightly higher cost than, for example, Ni-Mh, as well as sensitivity to overloads and violations of operating conditions - they can lead to fire and even explosion. However, most equipment for such batteries has built-in protective circuits; and if there are no such circuits, it is enough to be attentive to the operating mode, or buy a battery with a built-in protection circuit (see below).
— LiFePO4. A modification of lithium-ion technology (see relevant paragraph) developed and released to eliminate some of the shortcomings of Li-Ion. Lithium iron phosphate batteries provide high energy density, have a large number of charge/discharge cycles, and are characterized by chemical and thermal stability. In addition, LiFePO4 batteries withstand strong temperature fluctuations, support fast charging with high currents and are safe to use. Unlike the original Li-Ion technology, the likelihood of an “explosion” of a lithium iron phosphate battery when overloaded is practically reduced to zero. In general, such batteries effectively cope with high peak loads and are suitable for powering energy-intensive devices; they also maintain a stable operating voltage almost until discharge.
- Ni-Mh. An improved version of nickel-cadmium (Ni-Cd) batteries (see below), in which a special alloy that absorbs hydrogen is used for the anode instead of cadmium. This allowed us to achieve a number of advantages compared to the original Ni-Cd technology. Firstly, with the same sizes, the capacity has increased by 2 - 3 times; However, in terms of charge density, this type of battery is still noticeably inferior to lithium-ion batteries - however, it also costs much less. Secondly, Ni-Mh batteries are environmentally friendly and easy to recycle. Thirdly, the “memory effect” appears less frequently in them and is easier to eliminate. True, this technology does not allow achieving such high discharge currents as in nickel-cadmium batteries; However, Ni-Mh batteries still work great in high-power applications and are preferable to batteries for them (even high-quality alkaline ones - see below). A typical example of such an application is digital cameras. Also, one of the advantages of this technology is the stable voltage: it remains virtually unchanged almost the entire operating time, and drops noticeably only “at the last percent of the charge.” The disadvantages include a fairly high level of self-discharge; however, “low self-discharge” (Ni-MH LSD) batteries produced by some manufacturers do not have this drawback. Self-discharge in such power sources has been reduced so much that many of them go on sale charged and ready for use (like regular batteries) and retain a sufficient supply of energy for 1 - 2 years.
Note that Ni-Mh analogs of 1.5-volt batteries (for example, sizes AA and AAA) have a slightly lower nominal voltage - 1.2 V. However, most devices designed for similar sizes take this difference into account, and problems with interchangeability arise rarely.
- Ni-Cd. This battery production technology is often perceived as outdated in our time; however, similar elements continue to be produced and used. Nickel-cadmium batteries have a fairly low capacity, and are also highly susceptible to the “memory effect”: if the battery is regularly charged without completely discharging, its effective capacity decreases (as if the battery “remembers” to what level it is usually discharged, and accepts it as null). A similar phenomenon can occur with regular recharging - in particular, using inexpensive devices for trickle charging (compensating for the self-discharge of a fully charged battery). In addition, the production technology of Ni-Cd batteries is environmentally unsafe, and the batteries themselves are difficult to recycle and dispose of. Nevertheless, such power sources have a number of important (and in some situations, even fundamental) advantages over other rechargeable batteries. Firstly, Ni-Cd technology has practically no equal when operating at high discharge currents: even very significant loads are normally tolerated and have virtually no effect on the effective capacity of the battery (for more information on this effect, see “Capacity”). Secondly, batteries of this type are not afraid of deep overdischarge, high or low temperatures, and are also safe from mechanical damage. Thirdly, as they discharge, the voltage of nickel-cadmium batteries decreases very slowly (unlike, for example, alkaline disposable batteries). All these points make this type of battery perfect for devices with high power consumption - in particular, power tools and radio-controlled models.
Similar to Ni-Mh, similar elements in the “one and a half volt” standard size (for example, AA or AAA) produce not 1.5 V, but only 1.2 V.
- Ni-Zn. One of the oldest battery technologies in general, however, household power supplies of this type were only introduced in the 2000s. In many features, such elements are similar to the nickel-cadmium elements described above: in particular, they perfectly tolerate high discharge currents and are perfect for devices with significant energy consumption, and also maintain operating voltage for a long time as they are discharged. In addition, Ni-Zn batteries in “one and a half volt” sizes AA and AAA (and these are the majority) have not a lower, but an increased nominal voltage - 1.6 V, which allows them to be used without any restrictions as a more effective replacement for disposable batteries. The substances used in the design are environmentally friendly and easily recycled. The main disadvantage some time ago was the low service life (after 50 - 80 cycles the capacity decreased noticeably); this problem was solved, but only relatively recently. This is partly why so far (as of 2021) there are few such elements on the market.
Here are the main technologies used for disposable batteries :
- Salt. Also called “manganese-zinc”, based on the main metals used in the structure. The simplest technology used in full-size (not miniature) batteries; assumes an operating voltage of 1.5 V per cell - accordingly, elements with increased voltage like the 9-volt “Krona” are assembled from several cells. In any case, salt power supplies have a low capacity, their voltage decreases noticeably as they are discharged, and the high internal resistance does not allow the use of such batteries for loads with high power consumption. On the other hand, such elements are easy to manufacture, inexpensive and have a very low level of self-discharge. In light of the latter, for devices with relatively low power consumption (like remote controls), such batteries are even better suited than alkaline ones (see below): most of the energy of the alkaline element in this operating mode can be spent on self-discharge rather than powering the load. Many salt elements are labeled "general purpose".
- Alkaline. Technology for the production of disposable batteries, which involves the use of alkali in the form of an electrolyte (the second common name is alkaline). Very common in both full-size and miniature power supplies (see “Type Size”) with a nominal voltage of 1.5 V; Higher voltage batteries (for example, Krona) are made up of several one and a half volt cells. At the same time, the chemical composition of full-size and miniature versions is similar, but the general features (compared to analogues of the same sizes) will be different in both cases:
- Full-size alkaline batteries (such as AA and AAA) have more advanced performance characteristics than salt batteries. Firstly, their total capacity is noticeably higher - for example, for AA batteries it can exceed 3000 mAh (while for salt cells the maximum is about 900 mAh). Secondly, alkaline technology allows you to maintain operating voltage longer as you discharge. Thirdly, it reduces self-discharge and increases the shelf life of batteries. And the permissible temperature range for such batteries is wider, and the overall reliability is higher. The downside of these advantages is, first of all, the higher cost than that of salt power sources. In addition, it makes no sense to buy alkaline batteries for devices with low power consumption (such as remote controls): they will last longer than salt batteries, but this difference does not justify the difference in price, since a significant part of the alkaline power source is wasted in such conditions - for self-discharge.
Miniature alkaline button batteries, on the contrary, are a simpler and more affordable analogue of advanced silver-oxide cells. They use the LR marking (see "Size"), have a lower capacitance (usually 1.2 - 1.5 times lower than silver-oxide solutions in the same size), tend to rapidly decrease in voltage as they discharge, and also not designed for devices with high power consumption. On the other hand, for low-power loads (like a quartz wristwatch) such capabilities are more than enough; and alkaline tablets are much cheaper than “silver” tablets.
- Lithium. Lithium batteries are usually labeled CR; they can be either full-size or miniature (see “Size”). A distinctive feature of such batteries is that their voltage is 3 V per cell; this is usually the same overall voltage rating, with the exception of specific frame sizes CR-P2L or 2CR5, which use multiple cells.
Full-size batteries made using this technology were initially designed primarily for digital cameras and other devices with irregular power consumption and high power consumption. Miniature lithium “pills” are also well suited for similar applications (a typical example is car alarm key fobs, in which the transmitter is turned on for a low time, but requires a large amount of energy), but can also be installed in low-power loads. Another specific option for using them is as a backup power source for computers, tablets, digital cameras, etc., allowing you to save data about the power date/time and settings even when the main battery is disconnected. For example, a “classic of the genre” for powering BIOS memory on motherboards is the CR2032 battery. Due to the relatively high voltage, lithium “tablets” have a fairly significant actual capacity, so their service life in such a role is usually calculated in years and is often comparable to the service life of the device itself.
— Li-SOCl2. The so-called lithium-thionyl chloride technology is used to create disposable batteries with increased reliability, designed primarily for adverse operating conditions. Such batteries have a number of important practical advantages. Thus, their capacity ranges from 1200 mAh for the miniature 1/2 AA size to more than 35,000 mAh for the D size; and given that the nominal voltage is 3.6 V, the actual energy consumption is quite impressive. Lithium-thionyl chloride batteries can easily withstand high loads, including pulsed ones; maintain a stable voltage for a long time as the discharge progresses; have a wide range of permissible operating temperatures (from -60 °C to +85 °C in conventional models and from -40 °C +150 °C in high-temperature ones); equipped with built-in protection against overloads and low circuits; and even if such protection fails, the battery remains explosion- and fireproof and can be used even in rooms filled with flammable vapors. And self-discharge during storage does not exceed 1 - 2% per year, which ensures a long shelf life.
In general, LiSOCl2 batteries are an perfect option for devices that have relatively low constant power consumption and need to operate for a long time without additional maintenance. The main disadvantage of this technology is its very high cost, which limits its use mainly to specialized professional power supplies used for industrial equipment, in the military, aerospace industry, etc. It is also worth considering that although Li-SOCl2 can be made in “1.5-volt” standard sizes like AA, their rated voltage, even in such cases, will be the mentioned 3.6 V. And when turned on for the first time, the voltage usually turns out to be noticeably lower than the rated one ( about 2.5 V, or even less) - this is due to the chemical features of the technology; After a low time, this indicator returns to normal, however, this feature should be taken into account when used in certain types of devices.
— Silver-oxide. Technology used for advanced miniature batteries with a voltage of 1.5 V. These batteries use the same sizes as alkaline “tablets” (see above), but the markings are different: according to the generally accepted standard, silver-oxide cells are designated by the letters SR (alkaline - LR), and in our catalog a more specific standard is adopted as the main one - three digits with a three at the beginning, for example, “315” (it provides greater accuracy; for more details, see “Size”). In any case, due to the use of silver, such batteries are noticeably more expensive than their alkaline counterparts (for the same reason, silver-oxide technology is almost never used in full-size cells); however, the difference in price is offset by a number of practical advantages. One of the most noticeable is the high capacity (on average 1.5 times higher than that of alkaline “tablets” of the same size). In addition, this technology provides a more stable voltage, which decreases rather slowly as it is discharged, low internal resistance, and resistance to low-term high loads. Regarding the latter, it is worth noting that most silver-oxide elements are available in two specialization options: High Drain (for loads with uneven and high power consumption, for example, wireless calls, car alarm key fobs, etc.) and Low Drain (for loads with low and uniform power consumption, such as a quartz wristwatch). At the same time, similar batteries of the same size, but of different specialization, may have the same rated discharge power; however, HD versions are generally more resistant to uneven loading.
— Air-zinc. Quite a specific technology, popular mainly in compact PR series batteries for hearing aids (see “Size”). The chemical reaction that occurs in these batteries requires air; however, such batteries are sold hermetically sealed, and no reaction occurs in them. Thanks to this, self-discharge during storage is almost zero, and the shelf life is very respectable. Before use, you need to activate the power source by removing the plug installed on it and opening air access; Note that the plugs in zinc air “tablets” of different sizes differ in color, which allows you to distinguish them literally at first glance, without the need to read the small inscriptions on the case. After activation, the “life” of such a cell is several weeks - after which the electrolyte dries out and the battery becomes unusable, regardless of whether it was used as a power source or not. However, with constant use of the hearing aid, the charge runs out noticeably faster than the electrolyte dries out. Thus, the hearing aid customer can keep a decent supply of such elements with him and activate them one at a time, as needed, without fear that the rest will lose their properties.
