Autonomous power sources areone of the most useful inventions of mankind. What is a phone or radio that does not have rechargeable batteries installed? The arrangement of many devices, as well as the conditions for their use, do not always provide for the existence of a permanent network power supply, therefore such sources of electricity make it possible to operate in comfort practically anywhere in the world. After a small foreword, let's get down to the article.
What is a rechargeable battery?
Batteries accumulate electricity fromexternal power source, and then give it to connected consumers, so that they can do their work. So, when the devices work, chemical reactions constantly occur between the electrolyte and the electrode plates. By the way, a similar design is placed in the banks, from which the batteries are formed. The device of these designs provides for the creation of a voltage, usually 1.2-2 V, which is very small. Therefore, to increase the performance of power sources, different types of connection are used.
How do I discharge batteries?
Power supply data deviceprovides for connection to plus and minus. They function as follows: when a load is connected to the electrodes (as an example we can consider a light bulb), then a closed electrical circuit appears. The discharge current begins to flow through it. It is formed due to the motion of electrons, anions and cations. More detailed information on what and how it is, you can tell only on a concrete example.
Let's say that we have a battery, whereThe positive electrode is nickel oxide, in which graphite was added to increase conductivity. For a negative plate, sponge cadmium was used. So, when the discharge goes, the active oxygen particles are released and fall into the electrolyte. At the same time, they separate parts that go as electricity (the same electrons). Then the active oxygen particles are directed toward the negative plates, where they oxidize cadmium.
Battery operation while charging
Let's look at an example from the previoussubparagraph of the article. Here, the positive electrode will be enriched with oxygen, and pure cadmium will be restored to the negative electrode. Summing up, we can say that during the charge and discharge only the chemical composition of the electrodes changes. This does not apply to the electrolyte. But it can evaporate, which will negatively affect the battery life.
So, we have considered the principle of operation of any battery. Now let's find out how to improve their performance during operation.
Parallel connection
The magnitude of the current depends on a significant amountfactors. First of all, this means the construction, the materials used and their dimensions. The larger the area of the electrodes, the greater the current they will be able to withstand. This principle is used for the parallel connection of similar cans in batteries. This is done if it is necessary to increase the current value, which goes to the load. But along with this, it is necessary to raise the power of the source of energy.
Serial connection
You can see the use of this design,disassembling car batteries that are lead-acid. It should be said that this type is used not only in the device of a car battery, it is simply the most likely way to make out how this type of connection works. In this case, it is necessary to take care that there is no metallic contact, and there is a reliable galvanic coupling through the electrolyte. But it only needs to be understood in relation to this type. In other cases, the connection task will be implemented differently.
Types of batteries
- Lead acid.
- Lithium.
- Nickel-cadmium.
These are the most popular representatives. But in order to understand the possibilities, we suggest reading the list of materials that can act as electrodes:
- iron;
- lead;
- titanium;
- lithium;
- cadmium;
- cobalt;
- nickel;
- zinc;
- vanadium;
- silver;
- aluminum;
- a number of other elements, which, however, are very rare.
The use of different materials affectsthe resulting output characteristics and, therefore, on the scope. So, for example, li-ion batteries are used in computer and mobile devices. While nickel-cadmium is used as a replacement for standard galvanic cells. Theoretically, all types of batteries can work with any load. The only question is how justified is such an application.
Main characteristics
- Density refers to the characteristic ratio of the amount of energy to the volume or weight of the battery.
- Capacity is called the value of the maximum chargebattery, which he can give during the discharge process, until the lowest voltage is reached. This indicator is expressed in ampere-hours or pendants. The energy capacity may also be indicated. It is measured in watt-hours or joules. The task of such a capacity is to report the amount of energy that is given during the discharge until the minimum permissible voltage is reached.
- Temperature conditions affectelectrical properties of the battery. When there are serious deviations from the operating range recommended by the manufacturer, there is a high probability that the power supply will fail. This is explained by the fact that cold and heat affect the intensity of chemical reactions, as well as internal pressure.
- Self-discharge is called capacity loss, whichOccur after charging the battery when there is no load on the terminals. In many ways, this figure depends on the design and may increase if the isolation is broken.
These are the characteristics of the batteries andprovide us with the greatest interest. Of course, if you have to do something new and exclusive, previously unseen, you may need something else. But this is highly unlikely.
Device electrodes
You can find a hybrid design, where,except lead, antimony is added to the positive electrode, and calcium is added to the negative electrode. However, in such cases there is an increased consumption of water. To increase the resistance to corrosive processes, add tin or silver.
Electrodes are made with latticestructure, they are covered with a layer of active mass. The principle of operation of the battery is largely dependent on what material is used for the plates. We consider lead, which are easy to learn, but we always recommend against focusing on them.
Electrolyte
We consider all the same lead-acidbatteries. The electrolyte in which they are placed is most often sulfuric acid. It has a certain density, which can vary depending on the level of battery charge. In this case, the principle: the more, the higher. Over time, the electrolyte evaporates, and the battery capacity drops. On service life is affected by features of operation (observance of safety measures). In batteries, electrolyte can be of two types:
- liquid;
- in the form of impregnated special material.
At the moment, the most common type.
Battery operation
Diagram of the construction of the battery
We reviewed the basic information about the data.devices. Let's also pay attention to such a concept as a battery circuit. Indeed, within the framework of the article, it was covered only in passing. The battery of the modern scheme, according to history, was first created by the French physicist Gaston Plant. The area of his creation exceeded 10 square meters! Modern batteries, in fact, are simply significantly reduced and slightly modified copies of its battery. Only the body is visible to a person. It ensures the generality and integrity of the structure.
