DIY repair of maintenance-free car batteries

In detail: do-it-yourself repair of maintenance-free car batteries from a real master for the site my.housecope.com.

Car battery life is limited. When it fails, many simply buy a new one. And almost every battery can be rebuilt to make it last longer.

In a closed plastic container, there are positive and negative plates. A solution of hydrochloric acid, called an electrolyte, is poured inside, which forms a galvanic pair with lead plates. The terminals are supplied with current from a charger or generator. When enough of it has accumulated, the car's battery becomes a source of electricity. It is spent on starting the engine, operating instruments and lighting.

The generator replenishes energy losses, but over time, for various reasons, the accumulated reserve is not enough for a normal engine start. With proper operation, a time factor acts: the plates age. Under certain conditions, you can restore the battery, breathe new life into it. There are several methods of resuscitation. To choose the most suitable one, we first determine the reason for the inoperability.

The most common cause of death is sulfation of lead electrodes. The discharge is accompanied by the formation of plaque on the plates. If critical discharges are avoided, the crystals will dissolve during charging. But the causes of sulfation are not only deep discharges. It is also caused by other circumstances: constant undercharging, long storage in a discharged state.

Sulfation is fairly easy to identify visually. We unscrew the plugs and inspect the plates. A light white-brown bloom indicates the presence of a process. Other signs, including for maintenance-free acid batteries:

Video (click to play).

when charging, it begins to boil very quickly;
a fully charged battery does not turn the motor, it sits down in a few minutes from a regular light bulb;
white bloom on the body.

The second common malfunction is the destroyed plates, their crumbling. It is easily identified by the black color of the battery acid. If many gratings have crumbled, it is unlikely that it will be possible to revive such a source of tension.

Adjacent plates can be shorted. This occurs as a result of their deformation or shedding and sludge formed at the bottom. Closing occurs, as a rule, in one of the sections. A clear sign of a short circuit is that the electrolyte does not boil when charging in that bank or boils later, and the voltage indicator does not grow or grows very weakly.

Finally, acidic electrolyte can freeze. This happens when storing a highly discharged battery in cold weather. The ability to recover depends on the degree of frost damage. If the formed ice broke the plastic case, then the plates, probably, were warped, and they closed, after defrosting they will begin to crumble. If the case is intact, we defrost it in a warm place, and you can try to restore it.

We start any repairs with cleaning. We remove dirt from the surface, rinse with a solution of soda to neutralize the electrolyte, which is almost always present on the lid. We clean the terminals from plaque with medium-sized sandpaper. By the way, try how a car battery with clean terminals works. Often, their oxidized surface does not allow normal charging and the release of electricity.

If the battery is sulfated, and the plates did not crumble (the electrolyte is clean), then it can be restored using a simple charger.We need to break up the plaque on the plates. In the serious literature, pulsed charging, alternating with discharging, and strict adherence to modes are recommended. It is quite difficult to do it manually, and special chargers are expensive.

In practice, everything can be done much easier. We use the simplest memory with a slight alteration. We throw out the smoothing filters at the output of the step-down transformer. Instead, we install a diode rectifier. Each of the four diodes is rated for 10 A.

A hydrometer is required to monitor the density of the electrolyte. We check it in all banks, recording indicators. If there are 1.20 and below, it's time to act. We look at the level: if insufficient, add electrolyte of standard density so that it covers the plates by 1 cm. Connect the charger, set the current to 10% of the capacity. If we have a 60 Ah battery, then 6 A, maybe less: 3-5 A.

On a simple memory without fixing the parameters, the ammeter will first show a slight increase in current, then it will decrease, and the arrow will freeze in a certain position. From time to time we observe the process so as not to miss the beginning of the boil. After it, the current is reduced to 2 A, we continue to charge until it starts to boil again, and another 2 hours after that.

After the end, we measure the density: it does not grow much. We leave the battery disconnected from the charger for the same time that it was being charged. We measure again - we observe a slight increase in density. If it has not yet returned to normal, we repeat the cycle. It takes one day, usually recovery occurs after 3-4, sometimes you have to repeat 5-6 times.

Never add acid to a sulphated battery: it will only speed up the process and can lead to the death of the unit.

On sale there are automatic chargers such as "Cedar" and the like. During the charging process, they turn off on their own at the right time. We carry out a full charge beforehand to the maximum possible level. Then we turn it on in training mode for 3-5 days. In parallel with the charger, we catch the light bulb from the turning lamp, press the corresponding button. The process goes like this: charging goes on for about a minute, then discharging for 10 seconds. After training, we charge it completely.

Several schemes of home-made devices have been developed, which, like the factory ones, give out a short pulse charge current and conduct a small discharge in the gaps. The figure shows a diagram according to which it is not difficult to create such a device if you have knowledge of radio engineering.

We connect it to the terminals and observe the LEDs. Green light indicates readiness for operation, while yellow and red light indicates the need for desulfation. We carry it out like this:

we connect the device for a while until it is completely discharged (LED D1 goes out);
connect the charger and charge;
repeat desulfation until diodes D7, D8 light up green.

The charge-discharge process may have to be repeated many times. In especially advanced cases, it takes a week or more. The peculiarity of the device is that it consumes only 20 mA, it can be connected to the on-board network. It will constantly maintain the desired state of the battery without affecting the operation of the generator.

If there is no impulse memory, but we cannot do it ourselves, we try to use the manual mode. Let's take a simple charger with fixed settings. We set it to 14 V and 0.8 A, and leave it for 8-10 hours. The voltmeter will show the increased parameters. Be sure to leave it to stand for a day and charge it again, but with a current of 2 A. The voltage with the density will slightly increase.

We start the desulfation process. We connect the high beam bulb. For 6-8 hours we observe a voltage drop to 9 V, we do not allow it anymore - this is what we need. We'll have to control it with a voltmeter. We repeat the cycles:

night - we charge with a current of 0.8 A;
a day is worth;
night again - charging with a current of 2 A.

Depending on the degree of neglect, the process takes up to two weeks. A fully discharged battery is restored by 80%, which is enough to start the engine.

If the liquid in the cans has acquired an incomprehensible color: cloudy, black, it will have to be replaced. This happens in very old, unused batteries for a long time and in the event of a short circuit. In general, if the short circuit occurred due to warping of the gratings, then it can only be reanimated by physical intervention.

With old batteries, this was done simply: each can was separate. The short-circuited one was opened and new plates were installed. Now all the individual elements are enclosed in a common body, and such an intervention is difficult, but possible. We will tell you how to do this further, and now how to change the electrolyte.

A short circuit is determined by the black color, as already mentioned, and by charging. All banks begin to emit gas, but this does not happen in the short-circuited one. Then we drain the electrolyte by pulling it out with a pear. It is possible from one container, but better from all - filling with fresh electrolyte will not hurt. Then fill in distilled water, slightly shake the case and carefully drain. Do not turn it over so that the sludge does not get stuck between the plates. Repeat until the water is clear.

In a bank with short circuit, we resort to a more radical method. We drill a small hole 4–5 mm in the bottom of the case, drain the electrolyte and rinse with distilled water. All the sludge goes away, nothing remains. The hole is sealed with plastic using a soldering iron. If the plates are not warped, then it will be enough to change the electrolyte.

The further process is as follows:

Fill with electrolyte with a density of 1.28. It is possible to pre-dissolve a special additive for desulfation in it in two days. Let it stand for a day so that the air comes out.
We charge with a current of 0.1 A until the density is completely restored, making sure that there is no violent boiling and strong heating of the case. If necessary, turn it off, let it cool. We charge up to 14-15 V.
We look at the hydrometer readings, reduce the current and leave it for 2 hours. If during this time the density has not changed, stop charging.
We discharge with a current of 0.5 A to 10 Volts. If the indicator has dropped to this mark earlier than 8 hours, the cycle is repeated. If not, just charge up to nominal values.

And now about replacing the plates in a non-separable battery with your own hands. Cut the plastic around it from above. We disconnect the jumpers going to neighboring banks in any way: we unsolder or cut. We take out the bag and rinse well in water to wash off the acid residues. Now we are looking for where it closes. We examine the plates and dielectric. Objective: to find a particle that connects two plates.

Found - good, we remove it. First, you should rinse, removing all the dregs, set the bag in place. We restore the jumpers, glue the lid using glue, epoxy resin or melt it with a soldering iron. Fill with electrolyte and charge. If the plates are warped, you can use them from another old battery by choosing the least damaged package.

All work should be carried out with gloves and in a room with adequate ventilation, and preferably in the air: sulfuric acid and gases can be harmful to health.

If a strong voltage drop occurs in one of the six containers, the poles change their value during charging. A chain reaction is provoked, which leads to the same consequences in neighboring banks. The reasons for this situation are:

excessive sulfation, not amenable to recovery;
incorrect connection of the battery to the charging, which does not have protection against polarity reversal;
dirt on the case, causing constant self-discharge;
the discharge is not controlled, a strong discharge has occurred repeatedly;
errors in the operation of the generator and other power supply and consumption devices.

The polarity reversal technique is considered barbaric, but resuscitation is impossible in other ways. If it fails, there is nothing to regret, all the same, the battery had one way - disposal.

To begin with, we select the electrolyte from all the cans with a hydrometer and look at the indicators. We identify completely workers, sick and dead. The dead, as a rule, are few: one or two. To restore capacity, by and large, should only be with them. But the solid body does not allow for disassembly. You can use the technique described above to get to the faulty jar.

We will tell you how to reverse the polarity of all containers at home without resorting to disassembly:

First, we discharge the old battery to zero by connecting some kind of load, for example, a car light bulb. We measure the voltage: if something remains, we close the terminals.
In the gap of the negative terminal of the charger, we include the ballast resistance. A 50K resistor will do. It will protect the plates from short circuiting.
We connect the wires from the charger in reverse polarity. Positive - to "minus" of the battery, negative - to "plus".
We charge with a current of 10% of the capacity. The charge builds up quickly enough, but the case gets very hot.
We lower the current to 2 A and continue charging. Let it boil at a low current for 2 hours and turn it off.

We check the density: in normal containers it decreases, in dead containers it rises. Then we carry out a strong discharge by closing the terminals. We connect to the charger, observing the correct polarity. We charge according to the above scheme. For recovery, it is recommended to reverse the polarity twice.

You should not resort to polarity reversal when the following signs of a malfunction are present:

black electrolyte in cans;

short circuit;

insufficient level of density.

First, we apply the repair methods for a specific case, and if it does not help, we apply a polarity reversal.Do you still think that car diagnostics is difficult? If you are reading these lines, then you have an interest in doing something yourself in the car and really savebecause you already know that:

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Read also: DIY repair ford explorer

We have tested this scanner ourselves on different machines. and it showed excellent results, now we recommend it to EVERYONE! So that you do not fall for the Chinese counterfeit, we publish here a link to the official website of the AutoScanner.The car battery, like any other technical device, needs periodic maintenance. Many people today treat a car battery as a consumable. They do not service it, they operate it for 2-3 years and buy a new one. But a car battery can last much longer. With periodic maintenance, the service life is 5-6 years, and in some cases even longer. Therefore, if you do not have extra money, let's figure out how to service the car battery, and with what frequency.To properly service a car battery, you need to understand what factors affect its life. Then it will be clear what you need to pay attention to in the first place. The main factors that affect battery life are listed below.If a car battery is often discharged, this will greatly shorten its service life. Ideally, the battery should be kept charged at all times.That is, when the engine is started, it gives up part of the charge, and upon further charging from the generator during the trip, it compensates for these losses. But a modern car with a large number of current consumers simply does not have time to make up for the loss of charge. This is not at all facilitated by the driving mode in the urban cycle with frequent engine starts and many hours of downtime in traffic jams. Therefore, there is a need for periodic charging from the mains charger. If the battery is continuously discharged, the life of the vehicle's battery will be significantly reduced.
Back to content The temperature at which the battery is operated is also a factor affecting battery life. The starting power of a car battery largely depends on the temperature.As you know, a fully charged battery gives out its declared capacity at 15-20 degrees Celsius. When the temperature drops by one degree, the battery capacity decreases by 1 Ah.Frozen electrolyte in the batteryThis is an important point, since the condition of the battery strongly depends on the health of the car electrical network. It is especially important to have a working generator and voltage regulator. If these components do not work properly, then even with regular maintenance of the car battery, it will wear out ahead of time.Keep the car's electrical system in orderIf the voltage in the network is less than the norm, then the battery will be constantly in a discharged state. The negative consequences of this were discussed above. So, a faulty on-board network of a car significantly reduces the service life of the battery.
Back to content Corrosive processes also shorten the life of the vehicle's battery. Manufacturers are fighting this phenomenon by using various alloying additives. Corrosion is a natural process in all batteries. Motorists can be advised here to use high-quality electrolyte and distilled water when servicing the battery.If these consumables are of poor quality, then you risk only aggravating the corrosive phenomena. Here you can recommend buying distilled water from a pharmacy, not from car dealerships. There you run the risk of running into plain tap water.
Back to content Sulfation - the deposition of lead sulfate on the plates of the battery, which leads to a decrease in the capacity of the battery. The process of sulfation, like corrosion, is natural during the use and storage of batteries. But with proper and regular maintenance of the car battery, you can noticeably reduce the intensity of sulfation.Example of plate sulfationCar battery maintenance can be divided into diagnostics and, in fact, the service operations themselves with the battery. You can do the maintenance of the car battery with your own hands or entrust it to the service station workers, but you need to carry out the diagnostics of the car battery yourself. In this case, you will be aware of the current state of the battery.Car battery diagnostics include the following operations:

Checking the voltage at the battery terminals with an open circuit (that is, the battery is not connected to the car network);

Checking the voltage in the vehicle's on-board network with the engine running;

Checking the electrolyte level (on a car or on a removed battery);

Visual inspection (damage, contamination).

These operations should be performed without waiting for problems with the car's battery. They can be done with car maintenance activities such as checking the oil level, adding fluid to the washer reservoir, checking the tire pressure, and the like.
Back to content

Periodic and unscheduled (if necessary) charging of the battery with a network charger;

Checking and adjusting the density of the electrolyte;

Battery test with load plug;

Leakage current test;

Preventive works on desulfation.

To carry out the work, you will need the following devices, tools, materials:

multimeter (or voltmeter);

load fork;

hydrometer;

Charger;

glass or plastic tube;

pear;

electrolyte;

distilled water.

Attention! Always wear gloves and safety glasses when handling electrolyte. The electrolyte is an aqueous solution of sulfuric acid. The substance is corrosive and affects the skin and mucous membranes. Use personal protective equipment.Now let's take a closer look at how all this is done in practice.
Back to content Everything is simple here and you only need a multimeter or voltmeter to measure the voltage. The battery can be removed from the vehicle or simply disconnected from the terminals. The multimeter is switched to the voltage measurement mode, the probes are snapped onto the battery terminals (red for plus, black for minus). Nothing terrible will happen if the probes are connected the other way around. It's just that the voltage will be negative.Measuring battery voltage with a multimeter

Nevertheless, regular do-it-yourself car battery maintenance will significantly increase its resource with a minimum investment of time and money.

The need for routine maintenance of this kind is due to the following factors:

During the operation of the car, deviations of the charging parameters are possible due to generator malfunctions.
Prolonged standstill of the vehicle with the battery connected leads to a gradual loss of charge.
Lack of proper care of the battery can cause its malfunction and irreversible processes that make it impossible for its further use.

Modern car batteries are of two types: serviced and unattended (GOST 53165-2008 effective from 01.07.2009).

Video - how to service a car battery:

The first type of batteries needs maintenance in accordance with the recommendations developed by the manufacturer. The second type of batteries, despite the name, also needs periodic maintenance. The difference between them in this regard lies mainly in the volume of operations carried out.Good quality lead-acid batteries from well-known manufacturers have a lifespan of at least five years, provided they are carefully and promptly maintained. Sufficiently qualified maintenance of the car battery can be organized on its own without the involvement of specialists and contacting the service station. Image - DIY repair of maintenance-free car batteries

The composition of routine maintenance for each type of battery is significantly different.

Batteries of this type are becoming more widespread and are popular among motorists. Caring for a maintenance-free battery comes down to fairly simple steps and includes the following:

Inspection of the case for leaks.
Cleaning the drain holes of other battery parts from dirt.
Timely elimination of electrolyte leaks and acid neutralization with soda.
With a built-in hydrometer, the density of the liquid in the housing is continuously monitored.
Regular lubrication of the battery contacts to prevent damage.
Periodic checks of the voltage at the battery terminals with the engine running.

The latter procedure allows you to assess the level of charge that the generator provides. If the voltage is in the range from 12.5 to 14.5 V, this means that the unit is working properly.Deviations from the specified parameters indicate the wear of the generator and it is necessary to diagnose and eliminate the malfunction. After the repair, repeat the control measures in different operating modes, including with the headlights on and other consumers on.

Maintenance-free batteries do not have technological holes with plugs to control the level and add electrolyte to the required one. In the event of a critical drop in the liquid level or a decrease in density, the battery must be replaced with a serviceable one. If the car will not be used for a long time, then disconnect the ground. This action will avoid self-discharge.

Video - how to check the car battery:

A battery that is not used for a long time needs to be recharged periodically. For these purposes, special devices are used that lower the voltage to the required level and then switch to the battery charging mode. Modern chargers are mostly automatic and do not require human supervision during their use.

Devices of this type have holes for filling electrolyte, tightly closed with plugs. Maintenance of a car battery of this type is carried out in the same order as for a maintenance-free one, but at the same time it has a number of features.It is periodically necessary to monitor the electrolyte level in the jars and determine its density using a hydrometer. The device has a number of floats with different specific gravity and a bulb for filling the body.Video - how to check the density of the electrolyte in the battery:

Topping up electrolyte into cans is allowed only if clear signs of its leakage are detected. Usually, the stores offer pre-charged batteries, which allows them to be used immediately in the car.

Video - do it yourself car battery maintenance:

In the case of purchasing a dry-charged battery, it must be filled with electrolyte with a density of 1.27 g / cm 3 to the specified level. No earlier than 20 minutes later and no later than two hours, a hydrometer check is carried out. Image - DIY repair of maintenance-free car batteries

If the density drop does not exceed 0.03 g / cm 3, the battery can be installed on the car for operation. Otherwise, you need to connect the charger. The charge current should not exceed 10% of the nominal value, the procedure is carried out until the appearance of abundant gas evolution in the banks. After that, the density and level are re-controlled, if necessary, distilled water is added to the cans.

After that, the charger is reconnected for half an hour to evenly distribute the electrolyte throughout the entire volume of the cans.

The battery is now ready for use and can be installed on the vehicle for use.

Particular attention is paid to the condition of the battery in winter.A decrease in air temperature leads to a drop in the density of the electrolyte and the level of charge, which may not be enough to start the engine reliably.

A car battery that has not been used for a long time will lose charge. If the voltage at the terminals drops below 10.5 V, then this is not enough to start the engine and the battery must be charged.

Car battery recovery is carried out in several ways:

Carry out low current charging for a long time. If at the end of the process the density begins to increase, then there is hope for a positive result. As the charge continues, it may rise to an acceptable level.
If the battery plates are in working order, then it is allowed to increase the density of the electrolyte by adding sulfuric acid with a specific index of 1.4 g / cm 3.
A completely discharged battery can be reanimated in a specialized workshop. It uses special charging techniques in distilled water.

Video - car battery recovery after deep discharge:

High-quality restoration of a car battery after a deep discharge will save a lot of money, equal to the cost of buying a new battery. It should be remembered that the resource of such a battery is insignificant and a failure can occur at any time - especially during winter operation. Extremely low temperatures at low density of the electrolyte can cause it to freeze and destroy the plates.Regular care of the battery will prolong its life and avoid sulfatization of the plates or their mechanical destruction. Correct use of the battery significantly increases its resource, which makes it possible to reduce the cost of operating the car. Image - DIY repair of maintenance-free car batteries

You will learn how to paint alloy wheels with your own hands by reading the article.

Many people are helped by comments on prohibition signs.

Video - how to restore a maintenance-free BOSCH car battery:

Technologies do not stand still, and with their development new objects enter our life, which until recently seemed impossible. One of them is a power supply device for a car that does not require additional maintenance from the owner or specialists. The maintenance-free battery, as this device is commonly called, does seem like a huge improvement over previous types of car batteries. But is everything as rosy as it seems?

Maintenance-free batteries have been around since the late 1980s in the United States. Their fundamental design differences concern the material from which the jumpers and battery electrodes are made. The creation of an alloy containing small proportions of calcium and tin, instead of using pure lead, made it possible to create an energy source that loses its charge more slowly and almost does not require water to be poured into it. These designs could work up to 2 years without recharging and human intervention and quickly became known as "maintenance-free".

At the end of the 90s, the composition of the alloy from which these chargers are made changed again. It also included silver, antimony, and aluminum. The alloy is also cleaner than its predecessor. In parallel with the change in material, the design of the battery has also changed. It now has separators, a mechanism that retains lead sludge, and holes for filling in water and assessing the electrolyte level disappeared. As a matter of fact, the need for them has practically disappeared. Most modern car batteries are lead acid. This means that inside the device there are lead plates dipped in a mixture of water and sulfuric acid.

Which Battery Is Better - Maintainable or Maintenance Free? While unattended is a technologically more advanced device, each option has its own pros and cons.

Firstly, it is very difficult to disassemble the improved version of the battery, since it was created with the expectation of no refueling. This, in turn, creates certain difficulties when charging it. Secondly, and this is perhaps the main feature that distinguishes a maintenance-free battery, for correct operation it requires a constant voltage fluctuating within no more than 0.1 V. The correct operation of such a device is ensured by electronic adjustment mechanisms.

But this feature makes the installation of such a battery on cars of an old design or on heavily worn-out cars - a laborious task that requires additional costs. In order for a modern battery to operate on such a machine, it will be necessary to supply a modern generator capable of controlling charging and voltage using a microprocessor. Therefore, it may not be a good idea to install a maintenance-free battery on an old car.

The inability to open the battery case and check the electrolyte content in it determines the relationship of the car owner with the energy source of his car. Ideally, the only thing a car owner can and should do is charge a maintenance-free car battery.

Depending on the state of the battery, you can charge it in one of two ways:

Partial charge. This is a faster process and will take about three hours to reach 100% charge. If everything is configured correctly, control over the procedure is not required. To charge the battery in this way, you need a charger capable of supplying the same voltage at all times. Ideal settings are 13.9 - 14 volts and 25 amps.
Full charge. This process requires the possibility of a constant supply of current, whose strength will be equal to 10% of the battery capacity. This is a long procedure, usually lasting about a day and requiring constant monitoring. There is a small possibility that at the end of charging, some gas forms on the plates, after which the entire contents of the battery can go into a gaseous state. This is dangerous because there are no holes in the maintenance-free battery, which means an explosion could occur. After charging, you need to check the voltage at the terminals. The correct reading is 12 volts.

Despite the fact that modern batteries have the highest quality and reliability characteristics, they all suffer from one problem - vulnerability to cold in conditions of incomplete charge or almost complete discharge. Moreover, this leads not only to the fact that after a couple of trips with an incompletely charged battery at sub-zero temperatures, the car simply will not start, but also to a reduction in the service life of the battery itself. It is possible that in the end you will have to find a way to restore it.

For batteries of old models, this problem was solved easier - there was an instruction in which it was indicated how to control the ratio of water and sulfuric acid in the electrolyte. So the car could work without problems in the cold. For new batteries, water refilling is not structurally provided, and this creates certain problems.

To determine if the battery needs additional water, you first need to figure out how to check the electrolyte level in the battery. This is usually not difficult, since manufacturers either make a special transparent window, or leave the case of one of the batteries completely translucent.

After the need to increase the amount of water in the electrolyte became obvious, the next question arises - how to add distilled water to a maintenance-free car battery? Although this action was not foreseen by the manufacturers, folk ingenuity found a way out.

To carry out this operation you need:

distilled water;
a sharp and thin tool like an awl;
syringe, it is better to take with a long needle;
sealant.

Work order:

Remove the sticker from the battery cover. Do not open the lid itself - it will be very problematic to return it to its place later.
Carefully inspect the internal structure of the unit. Determine the location of the electrolyte cans and make holes above them as accurately as possible.
The first step is to tackle the jar, which has a density indicator. Add distilled water little by little through a syringe until the density indicator turns black or green. Then add another 20 ml.
Lower the needle, attached to the syringe, into the can and begin to gradually draw in the electrolyte inward. As soon as it appears in the cavity of the syringe, remove the syringe and mark the level of immersion of the needle with a marker.
Repeat the procedure with the rest of the jars, filling them with electrolyte up to the mark on the needle.
Shake the battery to mix the electrolyte well.
Seal the holes.

One of the questions asked by car owners with maintenance-free batteries is how long they last. The average battery life of this type, if it is in good conditions, can be up to 3 - 5 years. But for this, you need to know how to properly maintain the battery, apply this knowledge in practice, and prevent the battery from working for a long time in extreme conditions. The warranty period is usually 1 or 2 years.

In the event that a trouble still happened to the battery, the question arises of how to restore the device. There are several options for this procedure, but those involving a complete electrolyte change or filling the battery with stimulating solutions are not very suitable for maintenance-free devices. The best option in this case is several recharges with a weak current. The restoration of the battery in this case occurs due to the liquefaction of the densest areas of the electrolyte. The series of recharges will need to be repeated up to eight times, taking a break after the voltage reaches 2.5 volts, and the density is normalized.

Maintenance-free batteries are undeniably the most advanced option in car batteries. But, like any technique, they are imperfect. Maintaining this type of battery correctly and in a timely manner is an easier task than restoring it after breakdowns.

Video (click to play).