High current battery recovery. How to revive a car battery at home

The performance of a vehicle is highly dependent on technical condition battery. Once it is discharged or fails, and it becomes very difficult to operate the machine. Constantly pushing or pulling a vehicle in tow is not an option. Since replacing a power source is not cheap, the natural question arises of how to restore a car battery in an ordinary garage. Often, life extension is quite real.

About the design of acid batteries

Vehicles use 3 types of batteries - gel, alkaline and lead-acid. The first ones are considered relatively new, they are used infrequently and have not yet accumulated enough resources to talk about restoration. Alkaline batteries are found on commercial transport, electric forklifts and karakh. Overwhelming majority passenger cars equipped acid batteries, so their resuscitation should be considered in more detail.

A lead-acid battery is a sealed plastic case where the following elements are placed:

• positive electrodes (anodes) in the form of lead plates with an active filler, assembled into blocks (in jargon - cans);
• negative electrodes (cathodes) of identical design;
• separators - insulating partitions made of polymeric materials or fiberglass;
• connecting tires ending with two terminals for connecting the battery to the automobile electrical network;
• electrolyte is a solution of sulfuric acid.

Negative and positive electrodes are installed alternately, separators are placed between them to avoid short circuits. In the process of charging the battery, a chemical reaction occurs, which is why lead dioxide is deposited on the surface of the anodes - energy is accumulated.

After connecting consumers, the dioxide reacts with lead cathodes, forming on negative electrodes lead sulfate layer - energy is released. The gases released as a result of the reaction go outside through the valve and the vent.

Common Battery Failures

Restoring a car battery is not always possible and depends on the type of malfunction. The type of battery also plays a role:

• the serviced battery is equipped with plugs installed on top of each can;
• maintenance-free power supply features a one-piece plastic case - a monoblock without plugs.

If there are screw caps, you can check and correct or drain the liquid for repair. A sealed monoblock is reanimated in one way - by charging according to a certain algorithm, but a positive result is not guaranteed.

Battery failures are conditionally divided into 2 groups - external and internal. Each variety should be analyzed separately.

Elimination of external defects

During the operation of batteries, motorists have to deal with two external malfunctions: oxidation of lead terminals and cracks in the case. The latter arise for the following reasons:

• hull ruptured as a result mechanical damage(for example, falling battery);
• swelling of a discharged battery, located in severe frost;
• The plastic has become brittle with age.

Oxidation of the terminals prevents reliable contact of the source with the on-board network and often causes starter failure. The defect is “cured” by a simple cleaning with a large sandpaper, in advanced cases - a small file. In a similar way, the oxide layer is removed from contacts that are placed on the terminals and screwed on with bolts.

If a crack has formed in the housing, repair maintenance-free battery will not come out - there are no holes for emptying and filling the electrolyte. A battery equipped with plugs is repaired as follows:

1. Drain all cans of electrolytic fluid and rinse the inside of the case with distilled water so that the hot tool does not come into contact with acid when soldering.
2. Dry the case from the side of the crack, then carefully solder it along the entire length.
3. Cut out a patch of plastic and weld it over the crack, sealing the seams without gaps.
4. Another option is to use a glue gun. The defect needs to be slightly expanded, filled with a polymer composition, and then a patch is applied.

When finished, check the battery for leaks by filling it to the top with distilled water. If there are no leaks, fill the battery with electrolyte and try to charge. If the plate blocks are not damaged, the battery will "take" the charge and continue to serve on the car.

Note. If the case is cracked due to swelling or advanced age of the product, then it is unlikely that it will be possible to revive the battery by soldering the defect. The exact result will be shown only by charging performed after the crack is closed.

Internal problems

Majority internal faults definitely destroys the battery if the problem is detected too late. In the early stages, resuscitation is quite possible. The list of common problems looks like this:

• sulfation of electrodes - deposition on the plates of a thick layer of lead sulfate, which does not allow the electrolytic liquid to contact normally with the active filler;
• shedding of filler from lead gratings;
• short circuit of electrodes and blocks among themselves.

Reference. Short circuit of the plates - a consequence of shedding a large number active filler from gratings. The defect is critical - the battery cannot be restored.

The causes of these malfunctions are as follows:

• multiple full discharge lead acid battery"to zero";
• power supply operation with low level charging due to a malfunction of the generator or the electrical part of the car;
• long-term storage in a discharged state.

If the problem is detected at the last stage - deep sulfation, total shedding - it will not be possible to reanimate the car battery. An irreparable defect is diagnosed simply - the battery absolutely does not accept charging, the electrolyte constantly boils. In other cases, try to implement the battery restoration methods described below.

How to get rid of sulfation?

The first troubleshooting method is only suitable for serviced batteries. For implementation, you will need Charger, a device - an electrolyte density meter (hydrometer), a multimeter and a light bulb - a 12 V consumer.

Important! The lamp power is taken according to this calculation: the battery capacity (for example, 45 Ah) is multiplied by a factor of 0.1 and by the voltage value (12 volts). IN this case power was 45 x 0.1 x 12 = 54 watts.

Restoration of a faulty battery is carried out in the following order:

1. Fully charge the battery with a current equal to 10% of the power source capacity.
2. Check the density value in all jars with a hydrometer, it should be 1.27 units. If the density does not reach the indicated figure, add electrolyte and charge the battery for 30 minutes.
3. Connect a lamp to the terminals and discharge the battery, periodically measuring the voltage. Don't forget to note the start time of discharge.
4. When the voltage drops to 10.2 volts (full discharge), turn off the bulb. If the process took more than 8 hours, the battery is in an acceptable state (the discharge rate of a new battery is approximately 10 hours).
5. When finished, charge the battery to 100% again and put it on the car. Do not keep the power supply completely discharged.

The procedure allows you to partially or completely restore the lost battery capacity. To restore a battery with a maintenance-free case, use a different technique:

1. Look for a charger capable of delivering low currents - from 0.5 to 2 A with a periodic shutdown function.
2. Charge the battery for at least 2 days, periodically measuring the voltage.
3. Disconnect the charger and check the voltage for 2 hours. If it does not fall, try to put the battery on the car, otherwise charge further.

To achieve a positive result, the charging time can be 50 hours or more. It is preferable to use a charger that has a desulfation function - it will supply a current of 2 A at certain intervals.

Chemical Wash Method

This procedure is used to eliminate sulfation and quickly restore a serviced battery at home. You will need 2 commercially available reagents - Trilon B and an ammonia solution. The procedure is as follows:

1. Try to fully charge the battery, then drain all the electrolyte.
2. Rinse the battery with distilled water.
3. Prepare a solution by adding 5% ammonia and 2% Trilon B to the distillate (by volume of water).
4. Carefully pour the solution into the jars - a violent reaction will begin, accompanied by boiling and splashing.
5. When the liquid stops boiling, drain it and re-flush the battery.

After flushing, fill in the electrolyte and charge the battery again to the end. Flushing removes the excess lead sulfate layer, so battery capacity should be restored.

The last way to remove lead sulfate is to replace the electrolyte fluid with distilled water and charge at 14 volts for a long time. At the first stage, the battery is brought to a boil, then the voltage is reduced. The goal is to slowly dissolve sulfate in water. At the second stage, the distillate is changed, and the charging voltage and current are set to a minimum. The operation is considered successful if the density of the solution does not fall within 2-3 days. The duration of the procedure can take 3-4 weeks.

The task of increasing the life of car batteries has been faced by manufacturers of these devices from the very moment of their appearance. To date, battery production technologies have stepped far forward, effective methods for restoring these devices have been developed.

Typically, car batteries fail after two to three years of use. But at correct operation they can last much longer. If the battery began to charge poorly and hold a charge, in some cases it can be restored. And today we will try to answer the question of how to restore a car battery.

We note right away that it is not possible to restore the battery's performance in all cases. Below are the main malfunctions of this device with an indication of the possibility or impossibility of repairing the battery.

In order to better understand the information below, we invite the reader to familiarize themselves with the device of a car battery. It is clearly shown in this diagram:

The main causes of battery failure

The most common car battery problem is plate sulfation. At the same time, the battery capacity drops noticeably, and as a result, the device does not have enough power to turn the starter.

You can determine the sulfation of the plates by the following signs:

• Decreased capacity;
• electrolyte boiling;
• Plate overheating;
• Increased voltage on the electrodes.

Next common cause malfunctioning Battery - destruction and shedding of coal plates. This malfunction can be determined by the dark color of the electrolyte. Restoring the car battery in this case is possible, although not always.

The third common malfunction is related to the shorting of lead plates in one of the battery sections. It is quite easy to identify this failure. When charging, the faulty section will heat up excessively, and the electrolyte will boil away. It is possible to restore the battery in this case, although it is somewhat more difficult than in the first case. The solution to the problem is to replace the lead plates in the section, which is quite expensive, although cheaper than buying a new battery.

The fourth reason for battery malfunction is related to improper battery operation and storage. Known to be not fully charged accumulator battery at sub-zero temperature may freeze. Freezing may damage lead plates, as well as the body of the device. This can lead to short circuits in the device case and electrolyte boiling. In this case, unfortunately, the battery cannot be restored.

How to restore a car battery?

So, having found out the reasons, you can proceed to consider ways to restore the battery. As mentioned above, most complex malfunction is shedding and shorting of the plates. Just charging the battery with such a problem is completely pointless. Moreover, it may even worsen the situation. You need to act according to the following algorithm.

First, the battery is washed with distilled water. Flushing should be continued until no more cloudy water flows out of the device. Having finished with washing, it is necessary to inspect the plates. If they crumble, then, most likely, further work without replacing the plates will be meaningless.

If the plates are not badly damaged, then after removing the crumbled particles, you can get rid of the short circuit.

The next step is the desulfation of the plates, which involves the removal of salt deposits from the lead plates. To perform this operation, a desulfating additive to the electrolyte is used. Restoring a car battery in this case is performed as follows:

We dissolve the desulfatizing additive in a fresh electrolyte with a density of 1.28 g / cc in the amount indicated in the instructions for use of a particular agent. Usually, the process of complete dissolution of the additive in the electrolyte takes two days. After this time, the battery is filled with electrolyte. After pouring, make sure that the density of the electrolyte is 1.28 g/cc.

Having unscrewed all the plugs, we connect. To restore the battery capacity, we perform several full charge-discharge cycles. The battery is charged with a small current (about a tenth of the rated current). In the process of charging, we make sure that the battery does not heat up, and the electrolyte does not boil.

When the voltage at the battery terminals is 13.8-14.4 V, we reduce it by half charging current. After two hours, we measure the density of the electrolyte. If it remains at the nominal level, then the device has been successfully charged, and charging can be stopped.

If the density of the electrolyte does not correspond to the nominal, it should be corrected. For this purpose, distilled water or electrolyte is added to the battery. increased density. After that, the battery is discharged. To do this, a consumer of electricity (for example, a light bulb) is connected to the battery. When the voltage at the terminals drops to 10.2 V, the discharging process stops and a new battery charging cycle starts.

Important:

You can determine the battery capacity by calculating the battery discharge time. To do this, multiply the charge current by the time. If the battery capacity is below the nominal capacity, charge-discharge cycles should be carried out until the car battery is completely restored.

After restoring the battery capacity, add a little desulfating agent to the electrolyte and tighten the plugs. The battery, restored in the described way, should last a few more years.

The second way to restore the battery

The reader may find the described method rather long and labor-intensive. Yes, but the effort will pay off. long term operating a refurbished battery. Meanwhile, there is another method of battery recovery. So, how to restore a car battery quickly?

Using this method, the car battery can be restored in just one hour. The essence of the method is as follows:

The battery is charged to the maximum value. After that, the old electrolyte is drained, the battery is thoroughly washed with distilled water and filled with a special solution. This solution contains 5% ammonia and 2% Trilon B. Within 40-60 minutes, the process of desulfation of lead plates takes place.

In some cases, desulfation needs to be done multiple times, making car battery recovery a longer process. When desulfation is completed, the solution is drained, the battery is thoroughly washed with distilled water and filled with electrolyte. The restoration is completed by charging the battery with a nominal current.

Proper use of the battery

And in order not to have to wonder how to restore a car battery, it is worth adopting a few useful tips about caring for this device.

• At intervals of once every two to three months, check the level and density of the electrolyte;

• In severe frosts, it is worth raising the density of the electrolyte to 1.40 g / cc.

• It is necessary to charge the battery with a current ten times less than its capacity. For example, if the battery capacity is 60 A / h, charging should be carried out with a current of 5 amperes;

• If the air temperature is below -25 'C, do not leave the car overnight for open parking. At this temperature, the electrolyte in the battery can freeze, causing the battery to fail.

Subject to these simple tips, you will be able to significantly extend the life of the battery and do not have to wonder how to restore the car battery.

Each part or assembly in the car is responsible for a certain type of work. The main purpose of the battery is to run power unit as well as food onboard network car at idle engine. Like other systems and devices in vehicle The battery has a limited lifespan. In case of malfunctions in electrical system on a car or when the engine is difficult to start, the battery may lose its quality. However, do not rush to the store to buy new battery for auto. Knowing how to restore a car battery, you can reanimate the battery and significantly extend its life.

Many problems in the operation of the battery appear after improper maintenance or lack of care on the part of the car owner. Therefore, drivers should follow the recommendations of battery manufacturers, keep the device clean, and also perform periodic charging with a stationary device. In addition, the motorist must be aware of design features and the principle of operation of the power source.

Battery device and principle of operation

Since the invention of the battery, this device has been repeatedly modified and improved. All of them pursued the main goal - to increase the performance and durability of the battery. Today, many manufacturers use special materials that improve battery properties. But simple car enthusiast enough to know general ideas about the device and the principle of operation of the battery.

Externally, a car battery is a plastic closed container in which a set of negative and positive plates made of lead or alloys based on nickel, cadmium, etc. is hidden. Sulfuric acid is poured inside the battery, due to which a galvanic couple is formed. When current is applied to the battery terminals, electricity is stored. Having reached a certain capacity limit, the battery can itself become a source of current with a voltage of 12 V. Each time, including the car starter, the battery is discharged. But once the engine is running, serviceable generator must replenish the electricity supply. However, such an idyll is not always observed in the car. Therefore, the battery weakens after each start of the engine, and soon it does not have enough strength to rotate the starter. Repair of the car battery is carried out only after a thorough diagnosis by identifying the cause of the discharge.

Common battery problems

There are several common car battery problems. In some cases, the battery cannot be repaired, and sometimes the current source can be restored.

1. One of the most common causes of battery failure is plate sulphation. The symptoms of this "disease" look like this. The battery capacity drops rapidly, the power of the device is not enough to rotate the starter. In addition, overheating of the plates, boiling of the electrolyte and an increase in the voltage at the terminals are observed.
2. A common cause of battery failure is the integrity and shedding of carbon plates. This problem is easily identified by the dark color of sulfuric acid. It is not always possible to restore such a battery.
3. The next battery malfunction appears when adjacent lead plates located in the same section are closed. Such a problem is revealed quite simply. The electrolyte in this bank boils away, and the section itself becomes very hot. To restore the battery, it is necessary to open the battery and replace the damaged plates.
4. Incorrect operation of the battery, as well as errors in its storage, cause the electrolyte to freeze in frosty weather. As a result, not only lead plates are damaged, but also the battery case. With such breakdowns, the battery cannot be repaired.

Battery resuscitation methods

When the causes of the malfunctioning of the current source in the machine are clarified, it remains only to eliminate them. Get started with the simplest steps.

1. First of all, after removing the terminals from the battery, you need to do visual inspection device. If the lead electrodes are covered with a layer of white, blue or green powder, it is necessary to clean the contacts of the car battery with your own hands from these oxides. To do this, the loose mass is removed with a rag, and the conclusions themselves are cleaned with fine-grained sandpaper. Exactly bad contact can cause the starter to turn slowly.
2. The next step is to charge the battery, followed by discharging. Some modern pulse stationary devices are capable of simultaneously charging and discharging the battery, ridding the plates of sulfation at the initial stage. If the charger is an old model, then in this case the car battery is put on recharging for at least 10 hours at a current strength 10 times less than the battery capacity. For example, for a battery with a capacity of 75 A / h, a current of 7.5 A is set. After the process is completed, the battery must be completely discharged. To do this, a car light bulb is connected to it. As soon as it goes out, the battery is put back on charge. As a result of such successive cycles, it is possible to reanimate the car battery.
3. To eliminate a short circuit in the battery, you can use a special desulfating additive. It is added to the electrolyte with a density of 1.28 g/cu. see and leave for 2 days for complete dissolution. Then the electrolyte with the additive is poured into the battery, after which the density is measured again. If this indicator remains within 1.28, then it is necessary to charge and discharge the battery several times. If the electrolyte does not boil during charging, and the battery does not heat up, then the current can be halved. After 2 hours, it is necessary to measure the density of the electrolyte, and if it remains at the nominal level, charging stops. The battery has been successfully restored. When changing the density, water should be added to the electrolyte (if more than 1.28) or sulfuric acid (if less than 1.28). After adjusting the density, the battery is charged again.
4. Such a long resuscitation may not be suitable for some motorists. Question: how to restore a car battery at an accelerated pace? To do this, the battery is fully charged, after which the electrolyte is drained. The battery is washed with distilled water and then filled with a solution consisting of 2% Trilon B and 5% ammonia. After 1 hour, the solution is drained, sometimes you have to repeat the cleaning procedure. Again, the battery is washed with distilled water, fresh electrolyte is poured in and a full charge is performed.

Many problems in car battery It is easier to prevent than to eliminate. It is enough to monitor the cleanliness of the terminals and terminals, and once every 6 months to carry out full charge Battery using a stationary device, and the battery will thank its owner good work. And if the starter and engine are easy to rotate and start, then the battery life can be extended to 5-7 years.

In general, there can only be two situations:

1. The battery seems to work, but it drains very quickly.
2. The battery is dead and won't charge at all.

First situation: loss of capacity

In the first case, the battery capacity has dropped and you will have to put up with it. Full recovery batteries after deep discharge impossible (this applies to all Li-ion batteries: 18650, 14500, 10440, mobile phone batteries, etc.). Even theoretically, it is impossible to return the capacity of a lithium battery.

Decrease in capacity is an absolutely normal process. This happens during every charge/discharge cycle, no matter how well the battery is used. However, if deep discharges are often allowed during operation or, conversely, long overcharges (more than 500%), then the rate of capacity loss can increase significantly.

Recent studies have shown that lithium batteries lose their capacity even if they are not used at all. For example, during normal storage in warehouses. According to studies, the battery loses approximately 4-5% of its capacity per year.

Second situation: does not want to charge

Now consider the second case - the battery is not charging.

Usually this situation occurs when a device (phone, tablet, mp3 player) has been idle for a long time with a dead battery. Or if the lithium battery has undergone deep cooling.

In principle, there should be no problems with charging such batteries. Inside each battery - between the battery bank itself and the terminals that we see - there is a protection module that disconnects the bank from the terminals when the voltage drops below a certain threshold. Outwardly, this manifests itself as a complete absence of voltage at the battery output (zero volts).

In fact, as a rule, the voltage on the bank itself at this moment is about 2.4-2.8 Volts.

In the event of a battery blocking due to overload (short circuit in the load), the protection module also blocks the FET1 transistor. There is no difference from what the protection worked - from overdischarge or from a short circuit. There is only one result - an open transistor FET2 and a closed field worker FET1.

Thus, when deep discharged, the protection board lithium ion battery does not interfere with battery charging in any way.

The only problem is that some chargers think they are too smart and when they see that the battery is too low voltage(and in our case it will generally be equal to zero), they believe that some kind of unacceptable situation has occurred and completely refuse to give out the charging current.

This is done for security purposes only. The fact is that with an internal short circuit of the battery, it becomes dangerous to charge it - it can overheat and swell (with all sorts of special effects like electrolyte leakage, tablet cover extrusion, etc.). In the event of a break inside the battery, it becomes completely pointless to charge it. So the logic of such smart chargers is quite understandable and justified.

Read on to learn how to trick charging and restore the performance of a lithium battery after a deep discharge.

How to force it to charge?

Essentially, the recovery of lithium ion batteries after a deep discharge, it comes down to returning it to normal operation. It must be understood that this in no way compensates for the loss of capacity (this is impossible in principle).

In order to still force a too cunning charger to charge our very dead battery, it is necessary to make sure that the voltage on it exceeds a certain threshold. As a rule, 3.1-3.2 Volts is enough for the charger to consider the situation as normal and allow charging.

You can only raise the voltage on the battery with the help of a third-party (more stupid) charger. In the people it is called "push" the battery. To do this, simply connect an external power supply to the battery terminals, while limiting the maximum current.

For our purposes, any cell phone charger will do. Most often, modern chargers have an output in the form of a USB socket and, accordingly, give out 5V. We just have to pick up a resistor that limits the charge current.

The resistance of a resistor is calculated using Ohm's law. Let's take the worst-case scenario - the voltage on the internal bank of a lithium-ion battery is 2.0 Volts (we can't measure it without disassembling the battery, so we'll just assume that this is the case).

Then the difference between the power supply voltage and the battery voltage will be:

We calculate the resistance of the current-limiting resistor so that the charge current does not exceed 50 mA (this is quite enough for the initial charge and at the same time it is quite safe):

R = 3V / 0.050A = 60 Ohm

Now let's find out how much power will be dissipated on this resistor in the event of an internal short circuit of the battery (then all the voltage of the power supply will drop across the resistor):

P = (5V) 2 / 60 ohm = 0.42W

Thus, to restore the 18650 battery after a deep discharge, we take any 5V power supply, the nearest suitable resistor is 62 Ohm (0.5W) and connect it all to the battery as follows:

A power source is also suitable for a different voltage, it will be enough to recalculate the resistance and power of the limiting resistor. And you need to remember that in li-ion protection circuits, as a rule, field-effect transistors with a small drain-source voltage are used, so it is undesirable to take a power supply with a high output voltage.

Reliable contact when connecting wires to the 18650 battery terminals will help to provide small neodymium magnets.

If the charge does not go(the resistor does not heat up, but the battery has the full voltage of the power supply), then either the protection circuit went into very deep protection, or it simply failed, or there is an internal break.

Then you can try to remove the outer polymer shell of the battery and connect our impromptu charger directly to the bank. Plus to plus, minus to minus. If in this case the charge did not go, then the battery is cranked. But if you went, then you need to wait until the voltage rises to 3+ Volts and then you can charge it as usual (with regular charging).

Of course, with the help of this device, you can fully charge the battery, but then you will have to wait a very long time (after all, the charge current is very small). In addition, in this case, you will have to very tightly control the voltage on the bank, so as not to miss the moment when it becomes 4.2V there. And, if anyone does not know, the voltage towards the end of the charge will begin to rise very quickly!

Now the situation is different- the resistor, on the contrary, noticeably heats up, but there is zero voltage on the battery, which means that somewhere inside there is short circuit. We gut the battery, solder the protection module and try to charge the jar itself. If it works, then the protection board is faulty and must be replaced. However, you can use the battery without it.

As unfortunate as it may be, everything has its own lifespan. It is believed that the battery has a life of about three years, after which the battery is sent to a landfill, and a new battery takes its place in the car.

However, do not rush to say goodbye to the old battery ahead of time, as there are several ways to resuscitate it. It is with them that I would like to introduce you today.

The most common and favorite methods for resuscitating batteries by most car owners include:
1. Continuous charge of the battery with low current.
2. Battery charge in distilled water.
3. Maximum battery discharges by low currents.

Agree, the names of recovery methods give only superficial ideas about their essence. For achievement excellent result you need to get acquainted with these methods of resuscitation of the battery closer.

Continuous battery charging with low current

Using this simple method, you can restore life only to a battery with a slight and not chronic sulfation of the plates.

In order to give a second life to a battery, you need to:
1. Fill the battery with distilled water slightly above the level.
2. Turn on the battery for charging with a current of normal value (0.1 battery capacity).
3. As soon as gas formation in the battery becomes noticeable, the charge should be turned off for 20-30 minutes.
4. After a break, the battery must again be connected to a current, only this time reduced by ten times in comparison with the original, i.e. 0.01 of the battery capacity.
5. Having noticed increased gas formation on the plates of both polarities, it is necessary to disconnect the battery from the current and take a break for 15-20 minutes.

The fourth and fifth battery recovery steps should be repeated several times. Sometimes, in order for the battery to come to full combat readiness, it is necessary to repeat these procedures for several days in a row before starting to operate the battery at full capacity.

To avoid the inconvenience associated with battery operation, we recommend periodically checking the electrolyte level in the battery (the height of its layer should not be less than 5 mm above the upper edges of the plates), and if necessary, you can add distilled water. Make sure that no foreign matter gets into the battery. traces of oxidation on battery terminals and wires must be carefully removed.

Battery charge in distilled water

If the sulfation of the battery is deep, but not old, then you can try to restore the battery in the following way.
1. We discharge the battery to a voltage of 9 V.
2. Drain all the electrolyte solution and fill the battery with distilled water. We are waiting for about an hour.
3. After a pause in operation, turn on the battery for a charge. In this case, the voltage at each battery terminal must in no case exceed 11.5 V.
4. Gradually increase the charge. After the specific gravity of the solution has been increased to approximately 1.1-1.12, it is necessary to bring the charging current to a value equal to 0.1 of the battery capacity.
5. The battery should be charged in this way until a uniform gas evolution is noticeable on the plates of both polarities.
6. After that, it is necessary to discharge the battery for one and a half to two hours with a current equal to 0.2 of the discharge current, corresponding to a ten-hour battery discharge mode.

Steps 5 and 6 of battery recovery should be repeated several times. After the specific gravity of the solution does not stop increasing, the electrolyte level should be brought to normal and the battery is ready for use.

It is worth noting that this method is quite time-consuming, it can often take weeks to give the battery a second life.

Resuscitation of the battery by the method of maximum discharges with low currents

The battery recovery method, which will be discussed now, is suitable for batteries with old sulfation. Obviously, the process will be long and laborious, but worth it.

1. First of all, you need to charge the battery with a current equal to 0.2 * Q (where Q is the battery capacity).
2. After the voltage has reached 12V, the charging current should be reduced to the value calculated by the formula 0.05*Q.
3. The charge should be stopped when both the voltage and the weight of the electrolyte have reached stable values.
4. Let the battery rest for half an hour to an hour. Then again charge it with a small current until it “boils”.

This step should be repeated several times. You will understand that it is time to stop the procedure when the electrolyte starts to boil a few minutes after the start of charging.

After that, you should repeat the first stage of work, and after a couple of hours, continue to charge the battery in the indicated way. To restore battery performance, you may need to repeat the entire cycle of work up to 8 times.

Of course, restoring the battery on your own is a rather long and laborious process, but with a little effort you can significantly extend the life of the battery and save a significant amount.