Classification, types and sizes of batteries
Nowadays, batteries are the most common power sources for electronics and small appliances. The need for their replacement arises quite often. In order to make the best choice when buying a new galvanic cell, you should pay attention not only to the size of the batteries and the name of the manufacturer. In this article there will be answers to the following questions: what form are these sources of nutrition? What types of batteries are the size? How are the galvanic cells labeled and what should I look for when buying so that the power source lasts a long time?
Types of batteries
Classification of batteries is carried out depending on the materials from which their active components are made: anode, cathode and electrolyte.
There are five types of modern power sources:
The types of batteries by size will be listed below. And now in detail we will consider each of the specified classes of galvanic elements.
Salt batteries were created in the second half of the twentieth century. They replaced the previously existing manganese-zinc sources of power. The size of the batteries has not changed, but the technology of manufacturing these galvanic cells has become different. In saline sources of nutrition, an ammonium chloride solution is used as the electrolyte. It contains electrodes made of zinc and manganese oxide. The connection between the individual electrolytes is carried out by means of a salt bridge.
The main advantage of such batteries is their low cost. These galvanic cells are the cheapest among all the existing ones.
Disadvantages of salt batteries:
- in the discharge period, the voltage is significantly reduced;
- shelf life is small and is only 2 years;
- by the end of the guaranteed shelf life, the capacity is reduced by 30-40 percent;
- at a low temperature the capacity decreases to almost zero.
Such batteries were invented in 1964. Another name for these power sources is alkaline (from the English word alkaline, which in translation means exactly "alkaline").
The electrodes of such a battery are made of zinc and manganese dioxide. As the electrolyte alkaline hydroxide potassium appears.
To date, these batteries are the most common, because they are great for most electronic devices.
Advantages of alkaline power supplies:
- have a greater capacity in comparison with salt and, consequently, a longer service life;
- can operate at low ambient temperatures;
- have improved leak tightness, that is, the likelihood of leakage is reduced;
- have a longer shelf life, which is 5 years;
- have a reduced rate of self-discharge compared to salt batteries.
Disadvantages of alkaline power sources:
- the discharge period is characterized by a gradual decrease in the output voltage;
- the size of alkaline batteries is similar to the parameters of salt, but the cost and mass of alkaline power sources is higher.
In such a battery, the anode is made of zinc, the cathode is made of mercury oxide. The electrodes are separated by a separator and a diaphragm, which is impregnated with a 40% solution of potassium hydroxide. The alkali here is used as an electrolyte. Thanks to this kind of composition, this power source can work as a battery. But during cyclic operation, the galvanic cell degrades, its capacitance decreases.
Advantages of mercury batteries:
- stable voltage;
- high indicators of capacity and energy density;
- the possibility of working both at high and low ambient temperatures;
- long shelf life, which is 10 years.
Disadvantages of mercury energy sources:
- high price;
- the possibility of hazardous exposure to mercury vapors in case of depressurization;
- the need to establish a collection and disposal process.
In a silver battery for the production of an anode, zinc is used, for a cathode, silver oxide. The electrolyte is hydroxide of sodium or potassium.
This category includes battery for watches, the sizes of which will be given below. The advantages of silver power sources are as follows:
- stability of voltage;
- presence of high indicators of capacity and energy density;
- immunity to ambient temperature;
- long service life and storage.
The disadvantage of these batteries is their high cost.
In such a battery, the cathode is made of lithium. It is separated from the anode by a separator and diaphragm, which is impregnated with an organic electrolyte.
Advantages of lithium batteries:
- constant pressure;
- high capacity and energy density;
- independence of energy capacity from the load current;
- small mass;
- long shelf life, which is up to 12 years;
- immunity to temperature extremes.
The shortcomings of lithium batteries can only be attributed to their high cost.
As indicated above, power supplies have different chemical composition. Also, the shapes and sizes of the batteries differ substantially. Galvanic elements have different heights, diameters and stresses. Consider the classification of batteries in accordance with these parameters.
Classification of batteries by size
Depending on the voltage, height, diameter and shape, the power supplies can be systematized in a certain way. One of the most popular classification systems is the American one. It is presented in the figure below. This standardization is convenient, it is used in many countries.
According to the American system, power sources are classified as follows:
In addition to the class indicated in the table, the power sources also have a common name, which is used by the people. For example, the size of a AA battery is comparable to the size of a human finger, so the "folk" name of this galvanic cell is a "finger" battery, or "two A". But the power source C is referred to as "inch". The galvanic element D is called a "barrel". A battery AAA, the dimensions of which are similar to the parameters of the smallest finger of a person, is not in vain called "mischievous", or "three A". The power source PP3 was called the "crown".
Also in electronics are widely used miniature round batteries, the sizes and names of which differ in variety. More detailed information on silvery "pills" and classification of such power sources is given below.
Batteries "tablets": sizes and names
Another name for a miniature round battery is a dry cell. Such power sources consist of an anode made of silver oxide, a zinc cathode and an electrolyte. The latter is a mixture of salts, which has a pasty consistency.
Different manufacturers often assign to such power sources designations that differ from standard ones. Below is a classification table, which indicates the alternative names and sizes of watch batteries.
It is these miniature silver "tablets" that make the mechanisms of modern wrist watches work. When it comes time to replace the battery, you may be faced with the question, what kind of power supply is suitable in this situation? For example, if the element 399 was used in the clock, you can replace it with a miniature battery, which, depending on the manufacturer, may have the names V399, D399, LR57, LR57SW, LR927, LR927SW or L927E. Under such names, a "tablet" will be produced, whose height is 2.6 millimeters, and the diameter is 9.5.
The size of the batteries is not the only parameter that should be paid attention when buying power supplies. In order to learn how to decode the information that is located on the galvanic cells, you need to familiarize yourself with the basic principles of their marking.
Labeling of batteries
The International Electrotechnical Commission (IEC) has established a certain system of designations, according to which all batteries should be marked. The power supply casing should contain information on its power capacity, composition, size, class and voltage. On the example of the battery shown below, we will consider in more detail all the elements of the marking.
The information indicated on the power supply indicates the following:
- the electrical charge of the galvanic cell is 15 A * h;
- the power supply class is AA, that is, it is a "finger" battery;
- the voltage is 1.5 Volts.
And what does the inscription "LR6" mean? This, in fact, is the marking, which gives information about the chemical composition and class of the power source. Kinds of batteries have the following letter designations:
- salt - R;
- alkaline - LR;
- silver - SR;
- lithium - CR.
The battery classes are indicated by these figures:
Now you can decode the LR6 marking in the figure below. The letters here indicate that this is an alkaline galvanic cell, and the figure indicates the size of the "finger" battery, that is, indicates that the power source belongs to the AA class.
Scope and features of the choice of batteries
First of all, it should be noted that all galvanic cells meet the requirements of unification, that is, a consumer can easily replace the power source of one manufacturer with a similar battery of another. There is only one caveat: do not use in one device current sources manufactured by different firms or even more relevant to different types. This will significantly reduce battery life.
When selecting power sources, you should pay attention to the packaging. Often, the manufacturer indicates the device in which it is recommended to use these batteries. If such information is not provided, the tips below will help to make the right choice.
Salt batteries have a small capacity of 0.6-0.8 A * h and are used in devices with low power consumption. These can be remote controls, electronic thermometers, testers, floor scales or kitchen. Also, salt elements can be used as batteries for watches. The dimensions of such current sources are similar to the corresponding parameters of alkaline ones, however their application areas differ significantly. After all, if you use salt batteries in devices with an electric motor, flashlights or cameras, their service life can be only 20-30 minutes. Such galvanic cells are not designed for heavy loads.
Alkaline batteries have a sufficiently large capacity of 1.5-3.2 Ah. This allows you to successfully use them in devices that have increased power consumption. These devices include digital cameras with flash, flashlights, children's toys, office phones, computer mice, etc. Batteries designed specifically for cameras, give faster energy. This positively affects the speed of the cameras. If you use an alkaline power source in devices with low power consumption, the batteries will show an excellent result, their service life will be several years.
Twenty or thirty years ago, mercury batteries were widely used in devices such as electronic watches, pacemakers, hearing aids, military devices. To date, the use of these power sources is limited. In many countries it is forbidden to manufacture and operate such galvanic cells because mercury is a toxic substance. In the case of using these sources of current, it is necessary to organize their separate collection and disposal in accordance with safety requirements.
Silver batteries have not received a mass distribution because of the high cost of metal. However, miniature power supplies of this type are widely used in wrist watches, motherboards of laptops and computers, hearing aids, music cards, keyrings and other devices where it is impossible to use larger batteries.
Lithium batteries have a longer lifetime compared to even the best alkaline ones. Therefore, such power sources are used in devices that have high power consumption. It can be computer and photographic equipment, medical equipment.
A battery is a product that, despite its small size, can be dangerous. Do not disassemble the power source, throw it into the fire and, of course, try to recharge. In the network you can find tips on how to give the battery a second life. Do not try to conduct such experiments, because it can be dangerous.
When buying new batteries, you should pay attention not only to the manufacturer and the appropriate dimensions, but also to the chemical composition of power supplies. For this you need to be able to read the marking. Correctly selected batteries will serve a long and high quality.