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An article on how to choose a charger for car battery. Types of devices, important nuances of choice. At the end of the article - a video about a simple battery for your own hands.
The content of the article:
A modern car is equipped with an increasing number of devices that are powered by the on-board network. The role of the battery is to provide additional energy in situations where the generator does not cope with the loads. And rechargeable batteries, as a rule, are discharged at the most inopportune moment. Especially in the winter. And unlike the batteries of other electrical appliances, the battery for the car charger is not completed; it must be bought separately.
Varieties of chargers and their features
Z / u have several classifications and depending on their type are endowed with those or other qualities.
By the method of charge devices are divided into 3 categories:
Fixed Current Method
Such devices charge the battery to the limit and quickly enough. However, at the end of the procedure, the electrolyte has the property of overheating, and this reduces the battery life, provoking accelerated aging.
The method of constant voltage
In this case, the electrolyte maintains the desired temperature and it is not necessary to control the charging process, since in this scheme the device maintains a predetermined voltage level. The disadvantages are the decrease in voltage at the end of the process. This prevents the maximum possible battery charge.
Combined method
It combines the two above-described options - in the beginning the process goes on at a fixed value of the current, and at the end it goes on stabilizing the voltage. Such a tandem makes this type of instrument most effective and in demand.
By the method of charging z / u are divided into 2 categories:
Devices of transformer type
In everyday life they are unlikely to meet, since they have impressive dimensions and an equally impressive weight. Their purpose is to convert the current 220V into direct current (12V).
Pulse
The principle of operation is similar to the previous version, but this version is notable for compactness and low weight. Therefore, they are ideal for home use.
Depending on the model, impulse s / w can have:
- charging end indicator;
- indicator of incorrect connection (reverse polarity);
- function of protection against short circuits,
- automatic charging function;
- function of protection against polarity reversal, etc.
Transformer models are cheaper, but in addition to the shortcomings described above, they also require control during operation. Therefore, the pulse version is preferable.
Depending on the power source, z / u divided into 3 categories.
Powered by an electrical network
If the car is in the garage, where electricity is supplied, then this option is the easiest, convenient and reliable. In this case, the battery can be recharged while the machine is not in use.
Powered by a cigarette lighter
The disadvantages include the fact that for a long and / or intensive (in some models, the speed is regulated), there is a risk of overcharging the on-board network.
But in case of unforeseen situations, you can charge the battery at any time and in any place.
Powered by solar energy
Used rarely, because quality products are expensive, and cheap, as a rule, ineffective and short-lived.
And of course, they need sunlight to work. The solar model can be useful as an auxiliary option. For example, for those who have a network z / u, but often is "far from the outlet." For example, a fisherman, a lover of outdoor recreation or a hunter, this device will come in handy for sure.
According to the purpose, z / u subdivide into 2 types.
Charging-starting (or starting-charging)
Perform the function of not only recharging, but also starting the engine - they work in two modes: automatic and recoil mode overcurrent.
Some models are universal, with their help you can restore the ICE, charge the phone, laptop and other devices. It is enough to have a set of plugs of the right size.
It is important to follow the operating instructions and use the device for its intended purpose only after the terminals have been disconnected from the on-board network.
Charging-pre-starting
Used only to make up the battery, starting the engine with their help is impossible. This is due to the fact that the devices are characterized by a low value of the operating current. The plus is that when using them, there is no need to disconnect from the board.
What to consider when choosing
Before you start buying z / y, you should carefully study the documents for a specific battery and car (in particular the parameters of the board). This will avoid many difficulties and specify the requests. In fact, the information specified in the instructions is sufficient to select the appropriate device. However, there are some minor nuances that should be considered when choosing.
Counterfeit
There are few products that can win a competition with chargers in terms of the number of fakes. Therefore, it is best to purchase devices from authorized dealers or, at least, in retail outlets that enjoy a good reputation.
If you have decided on a particular brand, it is worthwhile to search the Internet for information about the features of the brand and its copies. A qualitative fake to determine in this way, perhaps, will not work, but to rid yourself of low-grade Asian consumer goods is quite realistic.
Capabilities
It is better to get a z / u with a small (it is small, too zealous not worth it) the current reserve. Such an acquisition has two advantages: the device does not have to work at the limit of its capabilities and if the battery is replaced with a larger capacity model, it will not be necessary to change the battery.
Indication
There are LED and instrument. LED does not differ this accuracy, but for domestic use it is quite enough.
Auto mode
If possible, preference should be given to the automated version. This will relieve the owner of the need to monitor the operation of the device and the possible consequences.
Manufacturer country
Many domestic products in terms of their characteristics are not inferior to foreign analogues, so it is worth taking a closer look at Russian products. It not only wins in price, but the risk of buying a counterfeit is almost zero. But even the inferior in quality domestic device is better than a fake prestigious brand.
Transmission
For cars with automatic transmissions, the charger-pre-start device will be the best option, since it does not need a mandatory cut-off of the power supply from the board.
Maintenance-free batteries
Protection against incorrect connection
In the case of a so-called polarity reversal, the function will not only prevent the battery failure, but also the battery itself.
Desulphurization function
Allows you to restore the battery with the formation of lead sulfate on the plates.
Rated charging current
The rated current is the current, which is 10% of the capacity of the battery. Having information about the battery (you can find it in the documents or on the case of the product), it is not difficult to calculate the required capacity of the battery.
For example, a charger of 6A is suitable for most batteries with a capacity of 60-70 Ah, which are equipped with cars. But for a truck or a jeep you have to look for a more powerful device.
Battery type
If you have a lead battery (WET), then it will need a special device. For batteries of other varieties, any z / y will do, however, their features should be taken into account.
Gel batteries (GEL) and batteries with electrolyte impregnation (AGM) are sensitive to temperature changes and overheating. They need a charger with current control function and an extended temperature range.
But it's best not to engage in experiments and purchase a rechargeable battery recommended by the manufacturer.
Conclusion
Some motorists rely on the generator, considering the state of the battery as a minor problem. However, the presence of a charger can greatly facilitate the life of the driver, because you never know how soon you need help with the battery and when it is completely discharged. And for this sometimes it is enough to leave the parking lights for the night switched on or put the car at the entrance for a while with the alarm activated.
Video about a simple battery for your own hands:
Types chargers
Chargers, based on their technical structure, can be divided into impulse and transformer. Transformers have been replaced more and more, as they have less efficiency, much more mass and dimensions. The transformer in such a device constitutes the lion's share of its mass. Pulse devices are much more compact, and cheaper, so they are increasingly popular with car owners these days. Although, in practice, transformer devices are more reliable and fault-tolerant, even at their production, the design of the device is given more attention.
Advantages of pulse devices
But the impulse charger for a car battery still has undeniable advantages and in addition to weight and price. They often put a lot of protective mechanisms, which greatly simplifies the life of car enthusiasts. On such devices, as a rule, there is a short circuit indication, it shows you that you have incorrectly connected the terminals, and so on. In general, the impulse charger for the car battery is as much as possible automated, it is much more difficult to spoil the battery when charging. The reverse side of such a decision is that in the event of a breakdown, an inexperienced owner will certainly not be able to repair the device himself. But in this case, the impulse charger for a car battery whose price is much lower than the transformer, often simply changes to a new one.
Principles of charging the battery
The rechargeable battery can be charged with three different principles, and these or other chargers are built on them:
- Charging constant voltage
- DC charging
- Charge by combined method
Charge by constant voltage
Charge by constant voltage is the most correct method, from a purely theoretical point of view. In the process of charging the battery, the number of amperes supplied in current must correspond to the remaining battery capacity in Ah, in a certain proportion, until the battery is fully charged. That is, at 100% charge of the battery the remaining capacity is zero, and hence the current should fall almost to zero. The method of charging with constant voltage is the longest, and has its drawbacks.
DC charging
- DC charging is much faster, but also more destructive for the battery.
- The current must be numerically equal to 10% of the battery capacity in Ah.
In both cases, the charger must necessarily control one of the parameters, otherwise the jumps in the stationary network will pass to the battery, and this affects it in the most pernicious way. In addition, you can not exceed the voltage 2,5V in each hotel bank - the plates just start to pour.
The impulse charger for a car battery usually has a very useful desulphation mode. In this case, the charging current is 10 times higher than the discharge current. Often, when the battery has been idle for a long time, a sediment settles on the bottom, and salts appear on the plates. This means that the battery charge has dropped dramatically. The puzzled car owner remembers that he was charging the battery 100%, and now he is sitting down - and decides to buy a new battery. The output in this situation is very simple - you only need to charge the battery in desulphation mode - everything will fall into place. Desulphation of storage batteries by means of charge-discharge cycles allows to increase their service life considerably.
Charging by combined method
It is important that the impulse chargers are able to turn off after the battery is fully charged. When the maximum level of charge reaches the required level in the banks, the device shuts down. This saves the car owner from unnecessary worries, the device does not need to be constantly monitored. Pulsed chargers were originally conceived to automatically switch modes. In them, as a rule, the combined method of charging is used - the most correct and sparing.
With the combined method, the probability of boiling of the battery is minimal, and gas evolution is minimized. While, at a constant current charge, the battery at the end of the process can trite to trite - and you can skip this moment. In impulse devices, there is a direct current first, and at the end of the process an alternating voltage is switched on - it drops to zero, but the voltage stabilizes. Thus, the pulse charger maximizes battery life, prolongs its service life.
Impulse chargers are rather complicated structures, they are built on the supply of a pulsating current. But at the same time, this complex hardware is very simple for the user, everything is automated in it. Modern technological processes made it possible to make production as inexpensive as possible. At the same time, the impulse charger for a car battery whose price is much lower than the transformer analogs is not something flimsy - it is reliable enough, its life cycle can reach tens of years. Low price, ease of use, careful attitude to a rechargeable battery, light weight and dimensions - all this makes the impulse charger an excellent candidate for purchase.
1. Introduction: modern chargers
A good charger is an integral part of a good battery system. The realities of the market are such that it is quite heavily filled with various chargers, most of them with a low price category. But the ideal situation is the maximum "kinship" of the battery and charger, they should work in pairs like a traction horse and a wagon. When developing and designing new battery models, the charger to them should be developed in parallel, and even in the first place. In fact, we often have a situation where the charger is already in a hurry and post factum, which of course is displayed on the functioning of the entire battery system. Some manufacturers often do not know the difficulties that can arise due to deficiencies in chargers, especially when charging under adverse conditions.
Figure 1: The battery and the charger should interact like a pulling horse and a wagon. Without each other, they will not provide the desired result.
Some chargers for lithium-ion batteries have a "wake up" function, which is necessary to restore the performance of batteries in which the voltage has fallen to a critical level due to excessive discharge. The reason for this state of the battery can be its long storage, during which the self-discharge reduced the voltage to the cut-off point. A normal charger can not charge such a battery, so it is often recognized as defective and discarded. The correct algorithm for restoring charging is to apply a small charge current to the battery, which will raise the voltage to a value of 2.2-2.9 V, which will activate the built-in protection circuit, after which normal charging will become possible. Care should be taken if the voltage of the lithium-ion battery falls below 1.5 V. This may indicate the presence of dendrites in it - the formations that jeopardize the safety of such a battery. (See BU-802b: What happens when the self-discharge of an electrical battery is increased, where the reasons for the increased self-discharge of a lithium-ion battery after a deep discharge are considered in figure 5. See also BU-808a: How to awaken a "sleeping" lithium-ion battery.)
Chargers for batteries based on lead and lithium operate according to a special algorithm - CC / CV (constant current / constant voltage - with English "direct current / constant voltage"). The value of the charging current is constant, but when the battery reaches a certain voltage value, the charging current decreases. Each electrochemical system has its own specific values of charging currents and voltages.
Nickel-based batteries are charged with direct current without being tied to the battery voltage. Full charge detection is detected by a slight drop in voltage after a period of steady rise. The charger should be able to quickly stop charging after indicating the full charge, since reloading can lead to unplanned situations - short-circuits or failure of elements. There is also a way to determine the total charge, based on a change in the rate of increase in the temperature of the battery. This charging method for nickel batteries is known as dT / dt and shows itself well in fast charging modes.
Increasing the temperature during charging is normal for a nickel battery, especially when the charge reaches 70 percent. The temperature rise is due to a decrease in the charging efficiency, therefore, the charging current must be reduced to prevent damage to the battery. The charger captures all these temperature changes and charges the required current. If you notice that a rechargeable battery still has a high temperature for a long time, it indicates an incorrect algorithm of the charger, and in that case it should be turned off to avoid damaging the battery.
NiCd and NiMH batteries should not be left connected to the charger unattended for weeks and months. If you do not need to use them, store them in a cool place and charge them before using them.
Lithium-based batteries should always remain cool when charging. If you notice that the temperature of the rechargeable battery has increased by more than 10 ° C compared to the ambient temperature, then the charge should be discontinued. Thanks to the built-in protection circuit, lithium-ion batteries can not be recharged, accordingly, it does not matter whether this battery is connected or disconnected from the charger. But if you need a long-term storage of a lithium-ion battery, it is better to place it in a cool place and charge it immediately before use.
A classic example of a charger is a rather slow device, which sometimes takes an entire night to charge the battery. This goes back to a long time when a simple charger for nickel-cadmium battery had a constant fixed charge strength of 0.1C (one tenth of the nominal capacity). Such chargers did not have the function of detecting a full charge, and it took 14 hours to 16 hours to reach it. Reaching the full charge of NiCd was recorded by a slight increase in the temperature of the battery. For a NiMH battery, this charging algorithm is not suitable because of the reduced ability to absorb excessive charge. Modern inexpensive chargers for AA, AAA and C sizes often use this algorithm, so in case of need of constant stand-by device readiness for operation of the device, it is necessary to stock up several sets of storage batteries. Also, when operating such a charger, it is necessary to monitor the temperature of the batteries.
Quick chargers have several advantages and the most obvious one is the charging speed. The possibility of realizing these advantages implies a closer connection between the charger and the battery. At a charge rate of 1C (See BU-402: What is the C-rating?), which is usually used by a fast charger, a fully discharged nickel-cadmium or nickel metal hydride battery can be charged in just one hour. As the battery approaches a full charge, some chargers for the nickel-cadmium electrochemical system reduce the charging current to avoid negative recharge effects. A fully charged battery switches the charger to a drip charging mode, also known as a serving charge. Most of the modern chargers for the nickel-cadmium electrochemical system have a charging algorithm for both nickel-metal hydride, which is distinguished by the absence of drip-charging mode.
The current in the idle mode of the charger should be as low as possible to save energy. There is a system of five-point evaluation of this energy efficiency, called Energy Star. The sense of evaluation consists in assigning a certain number of stars to the chargers for mobile phones and other gadgets. Five stars receive chargers with idle power of 30 mW or less; four stars are responsible for a range of 30-150 mW; three stars - 150-250 mW; two - 250-350 mW. Chargers with even greater idle power receive, respectively, the lowest rating - one star. The Energy Star is designed to reduce the power consumption of the charging devices, which for some reason remain unconnected to the mains during idle mode. The number of such chargers on our planet is estimated at one billion (!).
Use only a charger designed for a specific electrochemical system. Most chargers are designed for only one electrochemical system. Make sure that the battery voltage matches the charger. Do not charge the battery when the voltage is different.
The actual battery capacity may vary slightly from the nominal. Charging a larger battery takes more time. Do not use the battery charger with a battery that exceeds the charger specification by more than 25 percent.
Using a higher power charger reduces the charging time, but there are limitations as to how quickly the battery can be charged. Ultra-fast charging in any case causes some stress of the battery.
The charger for the lead-acid battery should be switched to the charge-keeping mode at full saturation, and for nickel charging is necessary after full charge. Maintaining charge and dropping charging are designed to compensate for self-discharge losses.
If necessary, the charger must have a temperature sensor to fix the full charge or battery failure.
Observe the temperature modes of charging. The lead-acid battery should remain slightly warm to the touch; nickel is heated to the end of the charge, but immediately cools down when fully charged. The temperature of the lithium-ion should not exceed the ambient temperature by more than 10 ° C.
Pay special attention to the temperature when using a dubious inexpensive charger.
Charge at room temperature. A lower temperature will affect the speed and quality of charging. Lithium-ion batteries can not be charged at negative temperatures.
annotation
Research plan
1. Problems charging the mobile phone ............................................. .... 3
2. Types of chargers .................................................................. 4
3. New charger .................................................................. 7
4. Charging time for different types of phones .......................................... .10
Conclusion ................................................................................................ .11
References .................................................................................... .... 12
ZUDILOV Viktor Sergeevich, TINO Nikolay Vladimirovich
DEVICE FOR CHARGING MOBILE PHONES
The supervisor of studies:, the teacher of physics,
MBOU School № 10
1. Problems charging the mobile phone.
Many of us have often faced the problem of charging a mobile phone battery during any trips. Often, going on the road, we simply forget to look at the display of the phone and make sure that its battery is charged. And only in the way it turns out that it is impossible to take an important call, because the phone is about to turn off. Some of us have just such long trips that even a fully charged battery of the phone can be discharged, and access to the network alternating current, by coincidence, no.
Accordingly, and the opportunity to use a regular charger, the phone kit is also not. Yes, you never know what other situations can happen in life. But to mobile phones, or rather to the constant availability of telephone communication, most of us are so used to that without it feel very uncomfortable, even if this connection at some time is not needed at all. Well, if in such situations, the "victim" is always available, for example, airborne network car. Then you can use the car charger, which today is abundantly available on the shelves of the respective stores.
But what to do if you need to recharge your mobile phone battery in other conditions, for example, in a hiking trip, where there are no familiar and at the same time affordable energy sources suitable for the phone's power supply? Fortunately, today there are already devices that can help us out in such extreme situations.
2. Types of chargers.
Everyone once encountered such a moment in life, when you wait for a very important phone call, and at the most crucial moment the phone turns off. And that this does not happen, you need to charge your phone more often.
The charger serves for charging, any kind of battery, whether it's a mobile phone battery, or a car battery. There are several types of chargers for cell phones. All chargers are divided into three main types. The simplest of them are not considered automatic, they usually use a power supply unit such as a transformer. They differ from others in that they are quite large in size and weight. Such charges are reliable, long-serving, but dangerous for accumulators due to the large capacity in comparison with them. Although such devices have gradually disappeared from human consumption.
The most popular for today is the charger for the phone impulsive and automatic, in which an electronic timer is built in. Its work consists in the following: first the timer in a mode of the maximum current it, actually, accumulates. This lasts for an average of four hours, then it transfers the accumulated current to the charging mode of the device already.
Consider the main types of chargers that exist today.
1. The network charger.
SZU (network charger) serves to charge the cell phone from the mains. All mobile phones are equipped with SZU. Network chargers are of two types: SZU is a charger that comes with the phone. Usual SZU are divided into 2 types: transformer and pulse. Pulse memory is afraid of power surges, which is usually the case when connecting other devices to the mains or in case of poor contact. The transformer storage is made with protection and has a current reserve. Without going into details electrical circuit of these charges, it can be unequivocally said that a transformer-type charging device is preferable to a pulse charger.
Now mainly Li-ion and Li-pol batteries are used, charging of these types of batteries does not require the chargers recommended for Ni-MH and Ni-Cd, therefore phone manufacturers began to equip with pulse chargers.
2. Car charger.
AMU (car charger) is used exclusively in the car. Car charger - This is a car voltage converter 12 volts in the required voltage to charge the mobile phone. Every motorist has an obligatory accessory for the mobile phone. The method of connecting the AMU is made to the cigarette lighter socket. The problem with these charges is that they do not give out the correct current at the output, which is not enough to power your phone.
3. Universal charger.
Universal chargers are quite a few varieties. One of the universal devices is the all-known charger called the "frog" in the people. Charger "frog" is a device that is suitable for charging almost all models of mobile phone batteries. The "frog" has two contacts + and - which connect to the same name hallmarks on the battery. The versatility of this charging is that these contacts can be moved to the desired brand of battery. Inserting the battery into the charging "frog" and connecting the contacts to the desired brands charge is connected to the mains. To universal chargers can be attributed and portable dynamo charging. Remember the flashlight - a dynamo that when you press the handle the light bulb starts to glow here according to this principle and the charging is working. The battery is charged by turning the knob or pressing the dynamo charging lever. Such charges are also equipped with a cable with various adapters for popular cell phone models.
4. Chargers powered by solar panels.
Chargers for solar batteries is intended for charging of accumulators of cellular telephones. The principle of operation of this charger. The charger converts sunlight into electricity, which charges the built-in rechargeable battery. From the built-in battery charger can charge a mobile phone battery, mp3 player, ipod, PDA.
5. Wireless charger.
The wireless charger is a platform on which the phone is charged. Simply put the phone on the platform without using any connecting wires. Wireless chargers work by induction. To use WildCharge wireless charging, you need to use a special adapter that connects to your phone. A range of mobile phones, mp3 players and other gadgets that can be charged on wireless platforms is quite limited.
3. New charger.
We offer a new type of charger for mobile phones, mp3 players and other gadgets that can be charged on wireless principles. It is based on the mechanical principle of producing electric current with the help of two electric motors.
The electrical diagram of this device consists of:
1. Six finger batteries (or batteries)
2. Connecting wires.
3. Two electric motors.
4. Output: USB socket.
5. Connecting Passive.
6. Body with two covers.
7. Handle to carry the device.
Photo 1. A working charger.
Electric motors play the role of an electric motor and generator direct current, which is necessary for charging the phone and other gadgets.
The electric generator is designed to convert mechanical energy into AC electric power. The main element of the electric generator is the anchor, which rotates inside the permanent magnetic field, created by the stator of the generator. At the armature of the generator there are placed current-carrying windings, the ends of which are connected to the contact rings. The contact rings, rotating together with the armature, slide over the conductive brushes.
If the frame is rotated in a magnetic field, thereby ensuring the intersection of the magnetic lines, then an electromotive force arises in it, under the action of which the frame begins to flow electricity. This phenomenon is called electromagnetic induction. The ends of the frame are connected to the contact rings, which rotate, slide over current-carrying brushes and transfer the generated electric energy to the consumer.
Electrical engine DC is designed for conversion electric power source of current in the mechanical. The electric motor consists of a rotor, a stator, conductive brushes and collector.
The rotor is a rotating movable part that carries the windings of the wire along which the electric current flows.
A starter is a fixed part that serves as a magnetic circuit, a magnetic field is created inside it.
The anchor is presented in the form of a frame made of a conductor. If the frame from the conductor, through which an electric current flows, is placed between the poles of the magnet, then the force moment becomes effective, causing the frame to rotate. To ensure a constant rotation direction, it is necessary that the current in the frame flows in the same direction.
In the DC motor this condition is ensured by a special
device - collector.
The collector is presented in the form of two semirings that rotate together with the frame and slide along the conductive brushes. The rotor of the motor is connected to the shaft, which transmits the rotation to other mechanisms by means of a belt drive.
Photo 2. Internal charging device.
4. Charging time for phones of different types.
To make sure that the proposed device is cost-effective, we have done experiments on charging this device with various types of phones.
Comparative table of positive and negative qualities of charging
devices.
Chargers from the solar battery. | Universal charger type "dynamo" | New charger |
Can charge the phone in the absence of AC and DC networks. | Can charge the phone in the absence of AC and DC networks. | Can charge the phone in the absence of AC and DC networks. |
Can not be charged in cloudy weather and at night | For charging, you need to turn the knob all the time, while talking on the phone, which is very inconvenient | Charging is enough for a limited number of devices, after which you need to change the batteries or recharge the batteries. |
During the work on the charger, the voltage and current ratings at the output were measured with a tester. The voltage was 5.5 Volts, which corresponds to the standard voltage on the charges made at the factory. The current strength is 70 m amperes, which is below the required value. It was decided to continue work on the charger and replace the second electric motor with a more powerful one.
Photo 3. Voltage and amperage measurement by the tester.
Conclusion:
1. The energy is supplied to the battery in small portions in order to maintain a charged state for a long time.
2. You can not be afraid to recharge the phone's battery, because all models are equipped with a protection circuit from this.
3. Charging is enough for a limited number of devices, after which you need to change the batteries or recharge the batteries.
4. The new charger can be made from the most handy materials. It's very simple. Easily repaired with breakage.
5. This device can be used if it is necessary to recharge the mobile phone's battery in the absence of AC and DC network, for example, in a camping trip where there are no familiar and at the same time affordable power sources suitable for powering the phone.
6. This device is much cheaper than all similar devices available for sale.
7. It is necessary to continue working on the device in order to achieve a standard output current.
Bibliography:
1. "Physics. Optics and waves "," Science "1983
3. "A great reference book on physics", "Drofa", 2004
4. http: // www. ***** / encyclopedia / 6677 /
5. "Elementary textbook of physics", "Science" 1980.
6. http:// mob- mobile. en/ statya/846.
Charger - device for charging electric batteries with external power; as a rule, from an alternating current network with a voltage of 220 volts.
The charger consists of:
- voltage converter (transformer, switching power supply);
- rectifier;
- the voltage regulator;
- current or charge control devices;
- Ammeter or LED indicators.
Types of chargers:
- Built-in;
- external.
Types of chargersfor nickel-cadmium and nickel-metal hydride batteries:
1. Chargers of normal (slow) charge
2. Fast Charge Chargers
3. Chargers of high-speed charge
Chargers of normal (slow) charge.
Use to charge only nickel-cadmium batteries. Chargers of this type, sometimes called night, they are the cheapest of all kinds of batteries. The current of normal charge is 0.1 s, the charge time is 14-16 hours, at such a low current and long charging time it is difficult to determine the end time of charge For this reason the battery readiness indicator in the chargers for normal charging is usually not available.
If the charging current is set correctly, a fully charged battery becomes slightly warm to the touch, and there is no need to immediately disconnect it from the charger. In it, the battery can remain for more than one day. But it's best to unplug the charger immediately after the end of the charge.
Do not use slow-charging chargers to charge low-capacity batteries, since they are designed to work with more powerful batteries. In this case, the battery will become warm when it reaches 70% of its capacity.
And in the event that an insufficiently powerful battery charger is used to charge a powerful battery, the battery will remain cold during the charging process and will never be charged to the end. Then it will lose some of its capacity.
Fast Charge Chargers.
Used for charging both nickel-cadmium and nickel-metal hydride batteries. They are characterized as middle-class chargers both in terms of charge speed and price. The charge of the batteries in them occurs during 3 - 6 hours by an electric current of about 0, 3C. As a necessary element, these chargers have a scheme for controlling the accumulators reaching a certain voltage at the end of the charge and turning them off at that moment. Chargers of a fast charge provide the best in comparison with devices of a slow charge service of accumulators. At the present time, they have given way to charging devices for high-speed charge.
Chargers of high-speed charge.
Used for charging both nickel-cadmium and nickel-metal hydride batteries. The main advantage of charging devices of high-speed charge is a shorter time of charge. Although due to the greater power of the voltage source and the need to use special control and control nodes, such chargers have the highest prices. The charging time in chargers of this type depends on the charging current, the degree of discharge of the batteries, their capacity and type. At a charge current of 1C, the discharged nickel-cadmium battery is charged on average in less than one hour. If the battery is fully charged, some of the chargers go into a recharging mode with a reduced charge current and with a trip on the timer signal.
Rules for the operation of chargers
- before switching on the charger, place it on a flat surface;
- Protect the charger from dust, dirt, food, liquids, overheating and overcooling, as well as from direct sunlight;
- when changing the storage conditions of the charger, which are accompanied by a sharp drop in temperature and humidity, condensation may form on the outside or inside it. Before operating the device, allow moisture to evaporate. This will help prevent the charger from going out of service.
- when transferring the charger from a cold environment to a warmer one or from a warm one to a cold one, do not turn on the power until the temperature of the device has come into line with the temperature of the medium;
- When disconnecting the cable from the mains, grasp the special loop on the plug. Do not pull on the cable. When disconnecting the connectors, keep them straight so that they do not bend the contacts. Similarly, before connecting the cable, make sure that the connectors are correctly oriented and aligned.
Storage of the charger
The charger in the original packaging should be stored in ventilated rooms at an air temperature of + 1 ° to + 40 ° C, relative humidity up to 80%, in the absence of gases and alkalis in the air, acid vapors that cause corrosion.
