With the advent of rechargeable batteries, many processes in life have become easier. Especially when it comes to AA batteries. Digital cameras, video cameras, and other newfangled gadgets can work up to 25 hours without recharging. And all this is achieved due to the electric current accumulated in the battery. Their equally important advantage is long service life, which is possible thanks to the presence of a charger. What they are like, how to choose the right one, and whether it is possible to assemble them yourself, we will find out further.
Pen-type batteries cannot last forever, requiring periodic recharging from a stationary power supply. The charger serves as a kind of conductor between the battery and the current, which the latter is able to accumulate for further use in gadgets. Since the market for models of devices operating on such batteries is extremely diverse, the batteries themselves differ accordingly (in power and composition). In this regard, chargers have their own design features that allow them to serve specific battery models.
The necessary structural elements for all types of chargers are:
The charging devices themselves have fairly compact dimensions. Their fundamental difference lies in the form of rechargeable batteries, which are:
The charger can be either highly specialized, designed exclusively for a specific type of battery, or it can be universal. The intellectual property of versatility is achieved by equipping it with a special adapter board that charges all types of batteries.
Charging is carried out by supplying current from the electrical network. The converter evaluates the amount of current received and then transfers it to the rectifier, which prevents sudden changes in voltage. The monitoring sensor indicates when the battery is fully charged. Most often this is an LED element that changes its color depending on the charge level.
In addition to charging, chargers can perform other functions that many users are not even aware of:
If you are going to buy batteries, but you do not yet have a charger, or you want to buy a charger to replace the old one, then the question inevitably arises - which charger to buy, what to choose from the huge variety?
Why do you need a quality charger?
The service life of high-quality NiMH batteries with proper care is on average 3-5 years. The capacity of modern batteries is comparable to the capacity of expensive alkaline (Alkaline) disposable batteries, but unlike them, batteries can be used from 500 to 3000 times. The benefits of buying batteries are obvious!
In order for batteries to last a long time and work efficiently, it is necessary to choose the right charger. A common mistake many buyers make is buying expensive high-quality batteries and buying a cheap charger or using an old one they bought a long time ago. As a result, even the most expensive batteries will quickly fail.
There are at least 3 reasons why you shouldn't skimp on a charger:
1. Cheap chargers can charge batteries extremely slowly - up to several days;
2. Also, cheap chargers can charge batteries very quickly, but at the same time they may not have proper protection against overheating and overcharging of batteries, which significantly reduces their service life.
3. Cheap chargers do not allow you to control the charging process and may not have automatic shutdown after the battery has finished charging.
You have to calculate the charging time “by eye”, this is not convenient and not accurate - the batteries can either be undercharged or overcharged;
All these factors negatively affect the quality of the batteries and also significantly reduce their service life.
Problems can be prevented or solved with a quality charger. Manufacturers offer a variety of chargers aimed at a wide range of consumers: from advanced users who want complete control of the battery charging process and parameters, to ordinary buyers who do not want to know anything about the battery charging process.
What should you consider when choosing a charger?
1. When choosing a charger, pay attention to the following important points:
Availability of independent channels for charging each battery separately
In addition, over time, the batteries in a pair begin to differ in capacity, which affects the duration and quality of operation of the pair. The difference in capacity can reach such an extent that, due to one undercharged battery, the pair practically stops working and it becomes impossible to use the batteries.
for AA/AAA+CROWN
for Li-ION+AA/AAA:
XTAR MC2 XTAR MC2S
TrastFire TR-001
4. Availability of the “discharge” function
The “discharge” function is a very useful function that allows you to extend the life of batteries and maintain high performance. The fact is that batteries are considered discharged when the voltage on them is 0.9 Volts, while many electronic devices turn off when the voltage on the battery drops only to 1.1 Volts or higher. When charging a battery that is not completely discharged, the “memory effect” appears over time, which consists of a loss of battery capacity and a decrease in its operating time.
To prevent the “memory effect”, it is recommended to completely discharge the battery before charging it. You can drain the battery using a flashlight or a child's motorized toy, but doing so runs the risk of over-discharging the battery. If the battery voltage drops below 0.9V, smart chargers may perceive it as faulty and not charge it.
Therefore, to discharge batteries, it is recommended to use chargers with the “Discharge” function.
When using batteries in toys or flashlights, do not allow the batteries to become deeply discharged. If you see that the battery is already low (the flashlight is dim, the motor in the toy is spinning weakly, or the sound is distorted), replace the batteries.
5. Availability of additional functions and features
Currently, the most popular are smart chargers that allow you to independently set battery charge and discharge currents, accelerate battery capacity, measure and restore battery capacity.
Buying such a charger makes sense if you constantly use batteries and you need to be confident in the capacity and performance of the batteries, or if you just like to experiment and explore. Also, such a charger is an excellent gift for anyone who uses batteries.
Smart chargers:
Separately, it is worth noting the smart chargers of the device, which are equipped with various additional accessories: AA and AAA batteries, travel bags, adapters. The quality of complete batteries and accessories is usually quite high, and the cost of batteries included is usually lower than the cost of similar batteries separately. Therefore, purchasing chargers with accessory kits can be very profitable.
Smart chargers with accessory kits:
Among the smart chargers, advanced chargers can be distinguished. These chargers are distinguished by the presence of additional functions and capabilities: screen backlight, measurement of internal battery resistance, a wide range of charge and discharge current settings, manual setting of the number of charge/discharge cycles for training/overclocking.
Advanced chargers:
6. Ability to work with batteries of different formats and sizes
If you use batteries of different types (Ni-MH, Li-ion) and different sizes, in order not to buy a separate charger for each type of battery, you can purchase a universal charger that is suitable for charging several types of batteries. Universal chargers are no worse than separate chargers for each type of battery. In terms of functionality, they can also be simple, which simply charge batteries, or advanced, which can charge, discharge, test and train batteries, and measure their capacity. Universal chargers combine the ability to work with Ni-MH batteries of sizes AA, AAA, C and Li-Ion batteries of sizes 18650, 14500, 16340, 26650, 20700, 21700, etc.
Universal chargers:
7. Ability to work with a large number of batteries
There are situations when it is necessary to charge many batteries at once - 6 -12 or more. It is quite obvious that using the most common chargers for 4 batteries in this case is inconvenient; the charging process takes a lot of time and requires additional attention. Using multiple chargers can also be an inconvenient solution to the problem.JBC-017
8. Super-fast chargers.
More and more Li-ION batteries with high load capacity are appearing on sale for electronic cigarettes, power tools, and powerful flashlights. In most cases, such batteries can be charged quickly without affecting their service life. For these purposes, special chargers are produced that allow the use of maximum charge currents for Li-ION batteries:MiBoxer C2-4000
(the paragraph below is intended only for Ni-MH batteries; modern Li-ION batteries can be charged by fast devices with currents of up to 4 amperes.)
Currently, you can find many chargers on the market that are called super-fast, ultra-fast, etc. This means that they are able to charge batteries quickly. What does this mean in practice? This means that chargers use high currents to charge batteries - 1000 mah per channel and above. Without temperature control of the batteries and cooling system, high charging currents cause the batteries to overheat, which has an extremely negative impact on their life expectancy. A high-quality super-fast charger must have a good cooling system, thermal sensors for monitoring battery temperature, and an overheating protection system. Otherwise, the lifespan of the batteries may be reduced by several times that stated by the manufacturer.
Special fast chargers with temperature and battery charge level control:
As a summary, we can say that to charge high-quality batteries, it is advisable to purchase a high-quality charger that will ensure a long battery life and high performance. Choose the optimal charger, which in its functionality will allow you to work with your batteries at the level you need.
Before purchasing, it is also advisable to consider whether additional functions may be useful to you in the future, even if you do not intend to use them now.
Thank you online store http://batterex.com.ua/
for the materials provided
Quite often, especially in the winter, motorists are faced with the problem of poor engine starting or the impossibility of starting it at all. As a rule, the cause in such cases is a dead battery. To quickly solve the problem, an automatic car battery can be used. You can learn more about what this device is and what its operating principle is in this article.
A smart charger has replaced traditional transformer charging. Such devices are characterized by small dimensions, as well as the presence of protection from dust, water, and short circuits. Such chargers are fully automated; therefore, during operation, the user does not need to monitor their operation. That is why they are considered intelligent.
But they generally work on the same principle as other memory devices. But you need to take into account that charging conditions may vary depending on the type of battery. For example, lead-acid batteries must be charged until they are completely discharged. Accordingly, in this case it is best to recharge the battery periodically. For alkaline batteries, they should be charged when completely discharged as this may affect their capacity.
Main features and advantages of smart chargers:
Smart charging is based on high-tech electronics that ensure optimal operation of the device. The device itself is characterized by small dimensions and is controlled using a special microprocessor. A controller is installed on the device board, which is configured to operate in different modes, while activating different protections. Accordingly, the user no longer needs to know how the charging procedure is carried out and calculate the time after which the device needs to be turned off.
The main characteristic of such a device is that for its proper operation, the car owner must know exactly what the capacity of the battery installed in his car is. The procedure itself will be fully controlled by the processor, which, in turn, is guided by the condition of the battery and also takes into account its wear. The main advantage of smart appliances is that they can charge all types of batteries when needed. And due to the fact that there is no coil in the design of the device, its size and weight are kept to a minimum - as a rule, it is about 0.6-1 kg (video author - Nikita Akimov).
As for the disadvantages, first of all, it is the impossibility of carrying out repairs at home. If the device fails for some reason, its repair will be possible only in a specialized center, since performing this task will require not only knowledge and experience, but also equipment and software.
The operating principle of an autocharger is somewhat different from traditional chargers. During the first 5 hours of operation, the device carries out basic charging cycles. After this time, the device checks the capacity and also evaluates the condition of the battery, after which it finishes charging. At the same time, it automatically sets all the necessary parameters in accordance with the actual state of the battery - this stage is completed within 2-3 hours.
It should also be noted that many smart chargers also have an adaptive charge function - when activated, it can take from 40 minutes to 1.5 hours to fully recharge. In this case, everything depends on the technical condition of the battery, as well as its capacity.
When the process is completed, the device should warn about this with a signal:
Upon completion of the procedure, the device will automatically switch to floating mode. A distinctive feature of an intelligent charger from a transistor charger is the ability to “treat” sulfated batteries.
In addition, such devices have a number of additional functions:
Let's consider several options for smart memory:
Price: $20.98
The device is called “Opus BT-C700”, it is the Chinese analogue of “BC-700” (La Crosse Technology). When purchasing, you had to specify the Euro or US plug.
The goods came for about a month. Came in a branded Chinese box with bubble wrap. Minimum set of power supply, charging itself and instructions in English.
This charger can separately charge 4 Ni-HM AA or AAA batteries (finger or little finger), I have not tested other types of batteries and do not intend to. The most recommended are Ni-MH. The charger can charge and discharge with several charge currents - the higher the current, the faster it charges, but the faster the battery deteriorates.
In addition, there are modes: Regeneration, Testing, Quick testing. Regeneration is a complete discharge and charging in order to restore part of the battery capacity. Testing to find out the current full capacity and full voltage of the battery. As you can see in my photos, the charger has a display backlight.
The “Mode” button sets the charger mode (first you need to hold it and then select the mode), and the “Current” button sets the charge or discharge current.
The “Display” button sequentially displays the operating parameters of the charger - charge current, current voltage, filled/drained capacity, charge/discharge time for each battery separately.
About Quick testing they write that in this mode the internal resistance of the batteries is determined. The measurement takes place within 10 seconds. The result is displayed in milliohms. If it shows 20-80 mOhm, the battery is of good quality. Batteries with readings above 500 mOhm are not suitable for applications with high current loads. Quick test mode can be used to test not only batteries, but also regular batteries.
In theory, the device is equipped with temperature sensors and reduces the current if the batteries overheat; there are ventilation holes in the bottom.
Bottom line: the thing is good, convenient) You can charge quickly or slowly and you can always see when the batteries are charged. In theory, it is possible to revive dead batteries. Overall, I'm pleased with this device.
This time - an intelligent charger for Ni-Mh batteries of AAA and AA sizes.
Why intellectual?
Unlike conventional chargers, which are sold cheaply by the Chinese or are included in kits such as “10 cheap batteries and a cheap charger for 2000 rubles”, and are charged in a “drip” way, this charger has a controller, which contains programs for fast charging batteries , and some other features - like determining capacity and “training” batteries to restore capacity.
99% of batteries sold in stores are AA or AAA form factors - Ni-MH. This is due to qualities that are more attractive to consumers - less noticeable memory effect, large capacity. True, along with these characteristics, the kit also comes with fast self-discharge (when, after some time, unused batteries have to be charged again).
LSD Ni-MH- Ni-MH with low self-discharge. Despite the intriguing abbreviation in the name, it is just an abbreviation for Low Self-Discharge :) Despite this, they have several more advantages - higher discharge currents, the ability to work at low temperatures, and an increased number of operating cycles.
More terms for those who have not read the article about charging lithium batteries.
Medium current charging with temperature control.
In this mode, the battery is charged with currents from 1/3C to 1/2C, which allows charging in an acceptable time - from 5 hours. When charging with such currents, the battery begins to heat up after the end of the charge, which can lead to its explosion. Therefore, in such chargers there is a temperature sensor next to the battery, which monitors a sharp increase in temperature and stops the charge. If charging is even a little “smarter”, it first discharges the battery to get rid of the memory effect, and then starts charging it. Some models also count the time from the start of charging, which allows you to indirectly judge the health of the battery - if charging ends in a much shorter time (an hour or an hour and a half), then the battery is faulty, which is indicated by charging.
High current charging with -ΔV and temperature control
The fastest charging technology. The battery charges at high currents (1C to 2C), allowing the battery to be charged in an hour or two. 
The basic principle of this technology is that before the end of the charge the voltage always increases, and immediately after a full charge it decreases. Not by much, by tens or even a few millivolts. The controller in the charger constantly monitors the voltage on the battery and, after a voltage jump down, reduces the charging current to approximately 10mA - to compensate for self-discharge - so that the batteries are always ready, even if they are left charging for a day.
There is a danger of not noticing this point, and seriously overheating the battery at such currents, so all chargers additionally have built-in temperature protection - thermal sensors for each battery, which temporarily turn off the charging process if the battery gets very hot.
As a rule, manufacturers do not limit themselves only to this mode - if you build in a controller, then you can add several more functions to it - current control, to determine the actual battery capacity, a training function - when the battery is charged and discharged several times to compensate for the memory effect, and others functions.
Using the Mode button you can select the operating mode - Charge, Discharge, Test, Refresh. To select, you need to hold the button for 2 seconds, after which you can select the mode with single presses. The first mode is Charge. It is installed by default and simply charges the batteries to full capacity. The second is Discharge, discharges and then charges the battery. The third one charges the battery if it was not charged, then discharges it, measuring the capacity in the process, then charges it again. Recovery - the fourth mode, cyclically discharges and charges the batteries until the capacity stops changing. 
As I understand it, the point of use is this - if you need to charge the batteries quickly, then you just need to insert them and select the charge current. And if time is of the essence - for example, if the batteries are useful only in the morning, then it is better to select the discharge or test mode - the batteries will be discharged, and then automatically fully charged. Thus, both the wolves are fed and the sheep are safe - the batteries will be charged without your intervention, and the discharge-charge scenario will eliminate the memory effect.
The testing mode takes longer because to determine the capacity, you must first fully charge the batteries. But after its completion, you will receive information about the battery capacity, and if something happens, you will be able to replace a suddenly dead battery in time (this is better than finding out about it during operation).
I talked about the main functions, everything else is in the manual: 
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