Serviceable and maintenance-free battery. What to choose? What is a maintenance-free battery and how to maintain it Topping up water or electrolyte

Modern car cannot be operated without a mobile power source. The battery not only allows you to start the car engine, but also takes on the main load at low generator speeds.

There are 2 main types of batteries: serviced and maintenance-free. What a maintenance-free chemical source of electricity is will be discussed in detail in this article.

Contents

What is a maintenance free battery

A maintenance-free battery is a product that does not have the ability to top up with distilled water. Such devices are safer during operation and charging, due to the reduction in the release of explosive gas, as well as the spillage of acid solution when tipped over.

As for the internal filling, a maintenance-free battery is no different from a serviced one. You can visually determine whether a battery belongs to the category of maintenance-free products by the absence of filler plugs.

Which one to choose, serviced or unserviced

Deciding on the type of battery to purchase can be very difficult. If the car previously had a serviceable battery installed, many car owners prefer not to change their habits. Serviced batteries have the following advantages:

It is possible to check the electrolyte level and its density.
If the level is insufficient, you can easily restore the battery’s functionality by adding the required amount of distilled water.

Unfortunately, this type of battery also has many disadvantages:

Evaporation of water in hot weather and when the battery is overcharged.
If you roll over on your side or drive too vigorously off-road, an electrolyte spill may occur.
Higher leakage current, especially if electrolyte was spilled on the upper outer plane, between the terminals, during refueling.
Additional time costs for preventive inspection and maintenance.

The maintenance-free battery has the following positive characteristics:

Set it and forget it;
No need to add water.

Flaws:

If the battery fails, it will not be possible to restore its functionality.
If the electrolyte boils away, it will not be possible to add distilled water without rough mechanical intervention;
Critical to overcharging and deep discharges.

Attention! If the vehicle has serious electrical problems, then maintenance free battery won't last long. In this case, it is better to purchase a serviced battery and carefully monitor the quality and level of electrolyte.

If there are no abnormalities in the vehicle’s on-board electrical network, then the most correct decision would be to purchase a maintenance-free device.

What types of maintenance-free batteries are there?

If you decide to purchase a maintenance-free battery, then you need to know that these devices differ not only in capacity and discharge current.

Lead calcium battery

A maintenance-free battery can be of the following types:

Calcium lead acid. The plates of this type of device are alloyed with calcium, as a result of which the material acquires properties such as vibration resistance and reduced corrosion effect. Also in calcium batteries there is a decrease in the process of self-discharge and boiling of the electrolyte.
A.G.M. It is an acid battery in which the electrolyte is contained in special fiberglass separators between the plates. This type is easier to tolerate deep discharges, and by reducing the intensity of sulfation of the plates, the service life can be increased to 10 years.
EFB. Design features This type of battery is that the thickness of the lead battery is significantly increased compared to conventional products. To reduce each plate is wrapped special material, which is impregnated with an acidic electrolyte. Thanks to the use of modern technologies, the service life ranges from 5 to 10 years.
GEL. Unlike other batteries, these have helium inside.

The above types maintenance-free batteries, will work without any complaints only with properly organized recharging, when the battery capacity drops below the established minimum limit for starting the engine.

Which chargers can charge maintenance-free batteries?

Considering the confined space in which the battery plates of a maintenance-free type are located, it is necessary to prevent significant overcharging of the battery.

Attention! To prevent the device from boiling, it is recommended to use an automatic charger.

The main advantage of this type of charger is the lack of human control during the entire charging time of the battery. The “smart” device itself will decide what voltage and current to apply to the battery terminals at the beginning of charging, in the middle of the cycle and at the last stage.

In the absence of an automatic device, you can restore the capacity with a conventional charger, but in this case, you will need to fully control the process.

For calcium batteries you can use any standard charger, for gel batteries you need a special charger.

How to charge a maintenance-free battery

Before charging a maintenance-free battery with a conventional charger, it is necessary to correctly determine the battery discharge level. Considering the fact that it is not possible to open such a battery to check the electrolyte level and its density, the degree of discharge is measured using multimedia. Also, many batteries are equipped with a charge indicator.

This device allows you to measure DC voltage with an accuracy of hundredths of a volt. If during diagnostics the voltage at the terminals is more than 12.6 V, then there is no need to charge the battery. When the voltage drops to 12 V, the battery charge will be only 50%, and if the voltage is less than 11.7 V, the battery is considered completely discharged.

The charging time when the battery is completely discharged is easy to calculate. The recommended charge current for all car batteries is 10% of the battery capacity. For example, if you need to restore a completely discharged battery with a capacity of 60 A/h, you will need to turn on the charger for 10 hours, and the charge current should be 6 amperes.

It is easy to calculate how much time will be required when the discharge is 50% or when the battery capacity is reduced by 30%. To do this, you need to divide the total battery capacity by 100 and multiply by the charge reduction percentage, then divide the resulting result by 6 for a 60 A/h battery and by 5.5 for a 55 A/h battery.

GEL battery

How to restore a maintenance-free battery

If a maintenance-free battery fails before the service life recommended by the manufacturer, then, in many cases, it is possible to restore the battery's performance to acceptable values. Considering the inability to disassemble a maintenance-free battery, you will have to pierce the top battery cover with an awl in 6 places. This way you can gain access to the electrolyte, which must be carefully drained from the battery.

At the next stage, distilled water is poured into the holes to the required level. The battery is then charged until gas is released. constant voltage 14 V. When the charging process is completed, the battery is left for a while so that the lead plates are slightly cleared of the sulfate film.

After a few days, the battery charging procedure is repeated, after which the water is drained and a working mixture of sulfuric acid and water is added. After charging, the battery can be installed in the car. The holes in the top cover should be sealed with any acid-resistant sealant.

Conclusion

The maintenance-free battery is ideal for use by novice drivers. Such a battery cannot be opened, so there is no danger of making mistakes during maintenance. For experienced drivers Those who know how and love to care for their iron horse, it is better to purchase a regular serviced battery, because carrying out infrequent and simple activities will significantly extend the battery life.

Have you ever had maintenance free battery? Share your experience in the comments, this will help make the article more complete and useful.

There are two types of starter batteries, which are commonly called serviced and maintenance-free. In general, as a rule, maintained batteries are low maintenance. This means that there is acid inside the battery and the average car enthusiast is not recommended to look inside the battery and come into contact with the chemically active liquid. Acid is a dangerous substance, since if it gets on clothes it causes tissue delamination, that is, you will ruin your clothes. In case of contact with skin or exposed areas of the body, rinse with water and preferably an alkaline solution. That’s why we don’t recommend getting inside the battery without certain knowledge and experience; it’s better to contact a service center.

THE DIFFERENCE BETWEEN A MAINTENANCED AND A MAINTENANCE-FREE BATTERY.
Now let's take a more specific look at what the difference is between a serviced and a maintenance-free battery. Those served have access to each section (bank). That is, there are 6 plugs on the top cover of the case. By unscrewing each plug, we have access to each battery section. This allows us to control the electrolyte level, control the color of the electrolyte and monitor the density of the electrolyte. Of course, this will help us conveniently carry out the necessary maintenance actions. Also, this allows us to manipulate the battery, if it is necessary to revive the battery, restore it, and bring it into proper condition. In serviceable batteries we have for this purpose more possibilities than unattended.

Maintenance free batteries. On the case of such a battery, the top cover is very tightly sealed, taped and does not have any holes that would allow us to get inside the battery. That is, these batteries are completely sealed and it is only possible to get inside if you drill a hole. And thus we can already see what is inside the battery.

They are called maintenance-free because we cannot perform any actions other than put them on charge. But, if suddenly, due to malfunction of the car’s electrical equipment, in particular the generator, a failure occurs and the battery is overcharged, then the water evaporates when it boils. Accordingly, we cannot add water to the battery. A maintenance-free battery may lose its properties and simply become unusable. Although, manufacturers of maintenance-free batteries claim that the valve system, which replaced the plugs, allows the evaporated liquid to be returned back to the battery sections, without manually adding water.

CHARGING THE SERVICED BATTERY.
The charging principles for maintenance-free and maintenance-free batteries are different. When charging a serviced battery, we connect the charger to the battery terminals. Only after this do we plug the charger into the outlet so that there is no spark. Using the current regulator, we set the current that we need to charge the battery.

This means that the optimal charging mode is a current of 1/10 of the battery capacity. If the battery has 60 ampere/hour, then the charging current should be about 6 A. If it is 100 A/h, the charging current is 10 A. Such currents are optimal for charging the battery.

When charging a serviced battery, the plugs must be unscrewed, since if the battery begins to charge, the voltage rises, a chemical reaction occurs and “boiling” begins. As a result of “boiling,” gases accumulate. And the vapors coming out can lead to an explosion when sparking. Therefore, you only need to charge the battery in a ventilated area where there is air circulation. And of course, try not to set anything on fire or smoke, so as not to cause any sparking while charging the battery. If the plugs are tightened, with increasing voltage and abundant accumulation of gases, if the bypass valves in the plugs do not operate, then the battery may explode!

CHARGING A MAINTENANCE FREE BATTERY.
If we charge a maintenance-free battery, the conditions are basically the same. In the same way, 1/10 of the battery capacity is charged with current. But you should be very careful about tension. Therefore, it is advisable to use only automatic chargers for charging maintenance-free batteries. Where the voltage is automatically adjusted when charging. But if this is not available, then you should set the charging voltage to no more than 14.5 V on a regular charger!

In these batteries, since the plugs are not unscrewed, there is an abundant accumulation of gases. The automatic charger will automatically cut off excessive voltage. And there will be no recharging.

RECHARGE THE BATTERY.
Overcharging is harmful, in particular because the electrolyte strongly “boils,” which evaporates water and the battery, as people say, becomes “dry.” That is, the entire conductor that is needed to conduct electric current evaporates. The plates are exposed, do not come into contact with the electrolyte, and this leads to the battery failing. That is, we are trying to start the engine, and chemical reaction doesn't fit at all.

Accordingly, when charging a serviced battery, it is imperative to monitor the electrolyte level and, if necessary, add distilled water.

UNDERCHARGED BATTERY.
Undercharging will lead to battery will fail over time. What could be the cause of undercharging? The cause of chronic undercharging may be faulty operation of the vehicle's electrical equipment (charging relay, generator). How is chronic undercharging harmful? The battery constantly works in “hunger” mode; it does not have time to recover. Considering the driving style of our drivers around the city, we have frequent car engine starts when driving short distances. And during such operation, the battery does not have time to fully charge, even with the generator working. And when the generator does not yet provide it with the required current, then the situation is completely bad. It can very soon fail and stop performing its functions.

The second very important point is that if the battery is dead, the process of sulfation of the plates begins to occur. Sulfate deposits prevent the passage of electrical current, the battery loses its capacity and starting current, and eventually it becomes unusable.

A gel battery for a car does not react so sharply to undercharging, but does not tolerate overcharging.

THAT'S REALLY ALL.
I HOPE THIS INFORMATION WILL BE USEFUL TO YOU AND EVERYTHING WILL BE OK WITH YOUR BATTERY.

If the engine is the heart of the car, then the battery is its irreplaceable energy source. Like any electrical appliance, it also breaks down. Many drivers ask questions about what is better - a serviced battery or a maintenance-free one, what are the pros and cons of this or that device, and which one is more economically feasible to purchase.

Electrical appliance of serviced type

Any electrical appliance has its own strengths and weaknesses. Every amateur driver will be able to clearly answer the question whether a maintenance-free or maintenance-free battery is better.

Positive aspects

In the case of a serviceable battery, the name itself speaks for itself, that is, it can be disassembled, a breakdown analysis can be carried out and failed elements can be replaced. The following work can be carried out in this type of battery:

check the electrolyte level in the banks;
check the density of the working solution;
visually analyze the color of the electrolyte and check for the presence of lead sulfate crystals in it;
the ability to inspect lead plates for damage;
see if the solution boils during charging.

All these features are a definite plus, since the driver can independently conduct various experiments and learn how to configure his battery so that it will last a long time and without failures. He can change the density of the electrolyte, add distiller to it, select the desired level of the working solution, and adjust its density according to the season and temperature conditions.

Negative points and inconveniences

Negative aspects of serviced batteries:

The leakage of the housing of such a battery constantly leads to evaporation of liquid. This process is activated during the hot season, so if you forget to add distiller to the device’s jars, the level of the solution in it may drop so low that it will be impossible to start the vehicle.
Constant evaporation of water leads to an increase in the concentration of sulfuric acid, which leads to wear of all battery elements and a decrease in its service life. Most often it is the lead plates that suffer.
When evaporating, acid enters the battery cover and a white coating forms on top of the device, which conducts current and can lead to an external partial short circuit of the positive and negative terminals. This process leads to rapid discharge of the entire battery.

The main problem with maintained batteries is constant monitoring of the electrolyte level. Great inconvenience arises in winter, when it is necessary to monitor not only the level of the solution, but also its density. It is recommended to check the level and recharge the battery once every 2 weeks.

You need to know that it is the distiller that needs to be added, and not the electrolyte, to the battery jars. This work should be carried out carefully, since when water gets into sulfuric acid, a large amount of energy is released in the form of heat, and the solution can splash out, burning your hands and even your face.

Therefore, such actions should be carried out carefully, wearing gloves and a mask on the face and adding water in small portions to the electrolyte.

Maintenance free battery

This type of battery is a sealed case, which is devoid of any plugs or covers; there are only terminals on its surface. It consists of 6 sections, and the principle of its operation is absolutely the same as for the serviced battery.

The main difference is the sealed housing. During operation, the electrolyte may boil and the distiller evaporate, but since the steam cannot leave the volumes of the body, it cools, condenses and flows down the walls. The result is a constant level of the working solution, and fluctuations in its density are minimal, that is, by using a sealed housing, it was possible to solve all the main problems of the electrical appliance being serviced. It is recommended for beginners to purchase it.

The negative points when using this type of battery are as follows:

The electrolyte in one or some banks may turn black, and this cannot be detected, since the case is made opaque on maintenance-free batteries. Cloudiness or blackening of the electrolyte occurs when the lead plates begin to deteriorate. This can happen at high temperatures and when the device is used incorrectly, for example: recharging it frequently summer time or partial formation of ice in it in winter.
Some sections or banks may fail, causing the battery to lose what it needs to operate the vehicle's systems. output voltage. On serviced batteries, you can immediately measure each cell with a voltmeter and localize the problem; this cannot be done on a sealed battery.
It is impossible to measure the density and level of the working solution.

To solve these problems, the battery is equipped with an emergency pressure relief valve and an indicator of electrolyte level and density. However, if the emergency release valve opens frequently, the solution will be lost in the form of steam, which cannot be added to the jars, which leads to a gradual weakening of the battery capacity.

Thus, if we answer the question of which battery is better, then for a beginner we should recommend this particular type of battery, which only needs to be used correctly, avoiding frequent recharging and deep discharge, and then it will last a long time.

Selecting a device type

Currently, about 80% of all batteries on sale are of the maintenance-free type, and if we consider the question in the general case, which battery is better - serviced or maintenance-free, then for all categories of drivers it is recommended to choose the latter type, since its correct operation ensures a long service life services.

On average, a well-maintained battery lasts about 2-3 years without interruption if it is treated correctly. A maintenance-free option can successfully perform its functions for 5-7 years. Such batteries are guaranteed from 24 to 36 months, but if you choose a maintenance-free type of battery, you should opt for well-known companies.

If you purchase inexpensive batteries with a sealed case, then most likely they will fail in 2-3 years, since such models use thin lead plates that quickly begin to deteriorate.

Cheap devices usually come with a warranty of up to 1 year.

Battery design

Before choosing a serviceable or maintenance-free battery, you should decide on the type of its design. Based on this indicator, there are 3 options:

If the driver has an old Lada, then the best solution would be to purchase a standard acid battery. For a new car it is preferable to take AGM batteries, which are capable of delivering a larger current at the start. As for gel batteries, they can be considered a luxury due to their high price. Also, these reliable devices are used to power powerful audio systems or to drive winches on those equipped with it. vehicles Oh. In the latter case, in addition to the helium battery, another battery is used, which powers the electronic components of the car.

Other indicators

When choosing a battery, you should pay attention to other properties. One of them is the inrush current, which is indicated on the label of the device case. It is measured according to the following standards:

EN: European standard indicating the maximum current in Amperes that a device can produce at a temperature of -18˚C for 10 seconds, while the voltage should not fall below 7.5 V.
SAE: This is an American standard that determines the same current at the same temperature, but for 30 seconds. at a voltage not lower than 7.2 V.
DIN: This is an industrial German standard according to which current is measured under the same conditions as in the SAE standard, only the voltage must not fall below 9 V.

It is the DIN standard that is preferable when choosing a powerful battery, since it undergoes more stringent testing compared to European and American standards. For example, 360 A according to the German standard corresponds to about 600 A according to EN. It is recommended to focus on this indicator if the battery is purchased for use in harsh winter conditions.

In addition to the starting current, important characteristic is the battery capacity. It is always written on the battery case, and you should purchase a new device with a capacity not less than the specified one.

The most common models are those that have this characteristic between 55 and 70 Ah.

The best battery brands

You can now find many companies and brands of batteries on the market. Such variety makes it difficult to choose. It is recommended to keep the following battery brands in mind when purchasing a new device (the price in rubles is indicated in brackets):

Lead-acid devices: Mutlu Silver Evolution 55 (3560), Aktex (AT) 55A3 (3620), Beast (3B) 55A3 (4200), Tyumen battery standard (3400), Tornado 55 A/h (2500).
AGM: Bosch 5951 (5700), Kainar Bars Premium 55 Ah (5250), Tudor AGM (8800), Banner Running Bull (9700).
Gel devices: Optima Yellow Top 55 Ah (17750).

From the data presented we can conclude that gel batteries are twice as more expensive devices AGM, and 5 times more expensive than conventional batteries.

A modern car cannot be operated without a mobile source of electricity. The battery not only allows you to start the car engine, but also takes on the main load at low generator speeds.

There are 2 main types of batteries: serviced and maintenance-free. What a maintenance-free chemical source of electricity is will be discussed in detail in this article.

What is a maintenance free battery

Which one to choose, serviced or unserviced

It is possible to check the electrolyte level and its density.
If the level is insufficient, you can easily restore the battery’s functionality by adding the required amount of distilled water.

Unfortunately, this type of battery also has many disadvantages:

Evaporation of water in hot weather and when the battery is overcharged.
If you roll over on your side or drive too vigorously off-road, an electrolyte spill may occur.
Higher leakage current, especially if electrolyte was spilled on the upper outer plane, between the terminals, during refueling.
Additional time costs for preventive inspection and maintenance.

Serviceable battery

The maintenance-free battery has the following positive characteristics:

Set it and forget it;
No need to add water.

If the battery fails, it will not be possible to restore its functionality.
If the electrolyte boils away, it will not be possible to add distilled water without rough mechanical intervention;
Critical to overcharging and deep discharges.

Attention! If your car has serious electrical problems, a maintenance-free battery will not last long. In this case, it is better to purchase a serviced battery and carefully monitor the quality and level of electrolyte.

If there are no abnormalities in the vehicle’s on-board electrical network, then the most correct decision would be to purchase a maintenance-free device.

What types of maintenance-free batteries are there?

If you decide to purchase a maintenance-free battery, then you need to know that these devices differ not only in capacity and discharge current.

Lead calcium battery

A maintenance-free battery can be of the following types:

Calcium lead acid. The plates of this type of device are alloyed with calcium, as a result of which the material acquires properties such as vibration resistance and reduced corrosion effect. Also in calcium batteries there is a decrease in the process of self-discharge and boiling of the electrolyte.
A.G.M. It is an acid battery in which the electrolyte is contained in special fiberglass separators between the plates. This type of maintenance-free battery can withstand deep discharges more easily, and by reducing the intensity of sulfation of the plates, the service life can be increased to 10 years.
EFB. The design features of this type of battery are that the thickness of lead batteries is significantly increased compared to conventional products. To reduce sulfation, each plate is wrapped in a special material, which is impregnated with an acidic electrolyte. Thanks to the use of modern technologies, the service life of an EFB battery ranges from 5 to 10 years.
GEL. Unlike other batteries, these have helium inside.

The above types of maintenance-free batteries will work without any complaints only with properly organized recharging, when the battery capacity drops below the established minimum limit for starting the engine.

Which chargers can charge maintenance-free batteries?

Considering the confined space in which the battery plates of a maintenance-free type are located, it is necessary to prevent significant overcharging of the battery.

Attention! To prevent the device from boiling, it is recommended to use an automatic charger.

In the absence of an automatic device, you can restore the capacity with a conventional charger, but in this case, you will need to fully control the process.

For calcium batteries, you can use any standard charger; for gel and AGM batteries, a special charger is required.

EFB battery

How to charge a maintenance-free battery

GEL battery

How to restore a maintenance-free battery

At the next stage, distilled water is poured into the holes to the required level. Then the battery is charged until gas is released at a constant voltage of 14 V. When the charging process is completed, the battery is left for a while so that the lead plates are slightly cleared of the sulfate film.

Conclusion

The maintenance-free battery is ideal for use by novice drivers. Such a battery cannot be opened, so there is no danger of making mistakes during maintenance. For experienced drivers who know and love to care for their iron horse, it is better to purchase a regular, serviceable battery, because carrying out infrequent and simple activities will significantly extend the battery life.

Have you ever had maintenance free battery? Share your experience in the comments, this will help make the article more complete and useful.

Electrical appliance of serviced type

Any electrical appliance has its strengths and weaknesses. Every amateur driver will be able to clearly answer the question whether a maintenance-free or maintenance-free battery is better.

Positive aspects

check the electrolyte level in the banks;
check the density of the working solution;
visually analyze the color of the electrolyte and check for the presence of lead sulfate crystals in it;
the ability to inspect lead plates for damage;
see if the solution boils during charging.

Negative points and inconveniences

Negative aspects of serviced batteries:

The leakage of the housing of such a battery constantly leads to evaporation of liquid. This process is activated during the hot season, so if you forget to add distiller to the device’s jars, the level of the solution in it may drop so low that it will be impossible to start the vehicle.
Constant evaporation of water leads to an increase in the concentration of sulfuric acid, which leads to wear of all battery elements and a decrease in its service life. Most often it is the lead plates that suffer.
When evaporating, acid enters the battery cover and a white coating forms on top of the device, which conducts current and can lead to an external partial short circuit of the positive and negative terminals. This process leads to rapid discharge of the entire battery.

Therefore, such actions should be carried out carefully, wearing gloves and a mask on the face and adding water in small portions to the electrolyte.

Maintenance free battery

The negative points when using this type of battery are as follows:

The electrolyte in one or some banks may turn black, and this cannot be detected, since the case is made opaque on maintenance-free batteries. Cloudiness or blackening of the electrolyte occurs when the lead plates begin to deteriorate. This can happen at high temperatures and due to improper use of the device, for example: frequent recharging in summer or partial formation of ice in it in winter.
Some sections or banks may fail, causing the battery to lose the output voltage necessary to operate the vehicle systems. On serviced batteries, you can immediately measure each cell with a voltmeter and localize the problem; this cannot be done on a sealed battery.
It is impossible to measure the density and level of the working solution.

Selecting a device type

If you purchase inexpensive batteries with a sealed case, then most likely they will fail in 2-3 years, since such models use thin lead plates that quickly begin to deteriorate.

Cheap devices usually come with a warranty of up to 1 year.

Battery design

Before choosing a serviceable one, you should decide on the type of its design. Based on this indicator, there are 3 options:

If the driver has an old Lada, then the best solution would be to purchase a standard acid battery. For a new car, it is preferable to take AGM batteries, which are capable of delivering a higher current at the start. As for gel batteries, they can be considered a luxury due to their high price. These reliable devices are also used to power powerful audio systems or to drive winches on vehicles equipped with them. In the latter case, in addition to the helium battery, another battery is used, which powers the electronic components of the car.

Other indicators

EN: European standard indicating the maximum current in Amperes that a device can produce at a temperature of -18˚C for 10 seconds, while the voltage should not fall below 7.5 V.
SAE: This is an American standard that determines the same current at the same temperature, but for 30 seconds. at a voltage not lower than 7.2 V.
DIN: This is an industrial German standard according to which current is measured under the same conditions as in the SAE standard, only the voltage must not fall below 9 V.

In addition to the starting current, an important characteristic is the battery capacity. It is always written on the battery case, and you should purchase a new device with a capacity not less than the specified one.

The most common models are those that have this characteristic between 55 and 70 Ah.

The best battery brands

Lead-acid devices: Mutlu Silver Evolution 55 (3560), Aktex (AT) 55A3 (3620), Beast (3B) 55A3 (4200), Tyumen battery standard (3400), Tornado 55 A/h (2500).
AGM: Bosch 5951 (5700), Kainar Bars Premium 55 Ah (5250), Tudor AGM (8800), Banner Running Bull (9700).
Gel devices: Optima Yellow Top 55 Ah (17750).

From the data presented, we can conclude that gel batteries are twice as expensive as AGM devices, and 5 times more expensive than conventional batteries.

These batteries come in different types: Liquid, Gel and AGM. Let's start with the fact that these are all acid batteries and the principle of their operation is no different from each other.

12 Volt Battery consists of six cells in which there are electrode blocks consisting of plates (grids) positive and negative with an active mass applied to them and separated from each other by a separator, all of this is filled with electrolyte. The process of formation (generation) of electricity occurs through chemical interaction between the active mass deposited on the grid and the electrolyte.

Basics fundamental difference Conventional liquid, Gel (GEL) and VRLA or SLA batteries created using AGM technology lies in the physical state of the electrolyte:

Conventional batteries have liquid electrolyte.
Gel (GEL) - electrolyte thickened to a non-fluid state using special additives.
VRLA or SLA, produced using AGM technology - the electrolyte is absorbed (soaked) into the separator.

The electrode grids that hold the active mass are doped with antimony and arsenic. Additives improve casting manufacturability, increase the hardness and corrosion resistance of electrodes. At the same time, antimony promotes increased consumption water and reducing the emf of the battery during operation.

Further development led to a decrease in the proportion of antimony in the composition of the alloy from which the gratings are cast. This led to the emergence of low-maintenance batteries (low-antimony technologies), and the battery life also increased. Then calcium replaced antimony from the negative plates. “Hybrid” batteries appeared and began to require topping up even less frequently.

The use of calcium in positive and negative plates (calcium technology) has led to the appearance of batteries that theoretically do not require topping up throughout their entire service life. However, such batteries fail from deep discharges. To increase durability, silver was added to the lead-calcium alloy of positive plates. The use of labyrinth caps and plugs, which condense the remaining evaporated water and return it back to the battery, has led to the appearance of completely maintenance-free batteries throughout their entire life.

Gel batteries appeared with the beginning of space exploration. The gel obtained by adding silicon dioxide to sulfuric acid makes it possible to achieve complete sealing of the battery, since all gas evolution occurs inside the pores in the gel mass. Such batteries have no equal in resistance to deep discharges; they are much more durable than traditional ones. But gel batteries have not become widespread among motorists due to very high requirements to on-board electrical equipment and due to a sharp drop in starting current in the cold.

Most modern technology(AGM) returned to liquid acid again, but now the electrolyte is held in the pores of a separator made of ultra-thin glass fibers. This design allows not only to seal the case, but also to maintain the functionality of the battery even if the outer shell is damaged. AGM batteries are insensitive to temperature fluctuations, very resistant to deep discharges, durable, vibration-resistant and can work even while lying on their side, but are afraid of overcharging.

FEATURES OF GEL BATTERIES

Gel electrolyte fills the space between the battery plates, but a separator is not excluded. Recombination of gases in gel batteries has an efficiency of up to 97%. The gel more effectively fixes the material of the plates, reducing their wear in deep discharge modes, therefore the cyclic life of gel batteries is 2-3 times higher than that of conventional ones, so it is advisable to use them in cases where such an application (cyclic mode with deep discharge) is in demand. Gel batteries can also be used in any position (except upside down) and have a slightly lower self-discharge, so it is preferable to use gel batteries in modes where the discharge is carried out at a low current for a long time.

In a gel electrolyte, ions have worse mobility (due to the higher density of the medium), which negatively affects the dynamic discharge and charging characteristics of gel batteries. Moreover, a temporary dip in voltage may occur with a sharp increase in load, which can lead to inappropriate behavior of the equipment; Therefore, caution should be exercised when using gel batteries in current control systems, etc. devices with switching of rapidly changing currents. Gel batteries are very sensitive to the quality of charging; batteries with gel inside can only be used where the on-board electrics allow very precise maintenance of the charge mode. Where there on domestic cars even with a working relay-regulator, the voltage “walks” from 13 to 16 volts! And on most foreign cars it’s not much better. And if the relay-regulator fails, then the gel battery can be immediately thrown away. It’s not for nothing that it says on it: the charge voltage is no more than 14.4 V. If it’s more, then the gel melts like jellied meat in the heat and is no longer restored. And here's another thing: real gel batteries, of course, can have a huge current, but only in the summer. The gel is already viscous, but in the cold it completely hardens. As a result, the characteristics drop by half or more.

Charging of gel batteries is limited to very low currents, otherwise there is a danger of “swelling” of the gel with excess gases due to lower recombination efficiency and limited thermal conductivity. It is preferable to power gel batteries from chargers with high quality voltage (stability, minimum ripple) to avoid overcharging and overheating, they cannot tolerate even short-term short circuits- any short circuit (for example, when installing a battery, you accidentally short-circuited two poles with a metal wrench for a split second) instantly disables the battery.

High vibrations cause the gel to liquefy and flow off the plates. As you can see, gel batteries are “better” (so to speak), only in terms of increased cyclic life and lower % self-discharge. In addition, this type of battery is the most expensive.

LEAD ACID, SEALED, VALVE-RECOMBINATION BATTERIES (VRLA or SLA)

VRLA(Valve Regulated Lead Acid) translated from English - Valve-Regulated Lead Acid;
SLA(Sealed Lead Acid) - Sealed Lead Acid;
AGM(Absorbent Glass Mat) is a manufacturing technology lead acid batteries, created by Gates Rubber Company engineers in the early 1970s. Porous glass fiber sorbent (AGM) is an absorbent separator used between the plates in a VRLA battery.

A special feature of VRLA batteries is the absence of the need to add water during the entire service life and the almost complete absence of the release of gases (hydrogen and oxygen) - products of electrolysis of water included in the electrolyte. Therefore, they are often called sealed maintenance-free. Minor maintenance, however, is necessary: first of all, visual inspection, wiping off dust, tightening connections and checking stress.

Due to the design features and composition of the materials of the plates, separators and electrolyte, the products of water electrolysis - hydrogen and oxygen molecules - in batteries of this type recombine, turning into water molecules and returning to the electrolyte.

The recombination coefficient under normal operating conditions is quite high and can reach >99%. Therefore, only a very small part of the non-recombined gases accumulates inside the battery housing and then, when a given pressure level is exceeded, is released into the atmosphere through special valves.

Advantages:

Vibration resistant, can be installed in any position and requires no maintenance, high inrush current.
Maintenance-free design.
The design is sealed and valve-regulated, preventing acid leakage and terminal corrosion.
Safer operation: with correct charging batteries eliminates the possibility of gas release and the risk of explosion.
The sealed design allows the battery to be installed in almost any position (upside down installation is not recommended, however).
Confident work with low temperatures(below - 40*C), low self-discharge (only 15 - 20% per year of inactivity), complete maintenance-free and long service life, up to 12 - 15 years.
Increased vibration resistance increases service life.
They provide a number of complete (70%) discharge cycles of about 500 times.

Flaws:

Should not be stored in a discharged state, the voltage should not fall below 10.8 V. Extremely sensitive to excess charge voltage.
To charge batteries made using AGM technology, it is advisable to use a special charger with appropriate charge parameters that differ from the charge of classic batteries with liquid electrolyte. AGM batteries are not as capricious as gel ones, but they also require attention to the condition of the generator and relay regulator. The fact is that in batteries of this type there is very little electrolyte, and if it boils away, it is impossible to top it up.
High price.

Batteries produced using AGM technology are manufactured in a spiral or flat-plate configuration. Spiral elements have a larger surface contact area, which makes it possible to produce high currents for a short time and charge faster. However, the downside is that the battery's specific capacity (the ratio of electrical capacity to size) is reduced compared to a flat configuration. Both technologies are promising. Currently the most common car batteries AGM with flat block configuration. SpiraCell spiral blocks are patented by Johnson Controls for the Optima series and cannot be used without their permission, unlike flat blocks. Spiral batteries have higher current efficiency and lower internal resistance due to the larger working surface of the plates at the same external dimensions batteries. In simple terms, they are more powerful.

Lead-acid batteries with bound electrolyte, made using AGM technology, appeared about 40 years ago - they were invented to operate in buffer mode in stationary uninterruptible power supply systems. Such batteries are good from a safety point of view, since they practically do not emit gases formed during charging into the atmosphere. In the 90s of the last century, AGM technology took root in motorsports. Firstly, again because of safety - now thanks to the completely sealed battery case, which prevents leakage of electrolyte in the event of an accident. And secondly, due to their compactness - thanks to the low resistance of separators not insulating, but separators impregnated with electrolyte, they produce a large starting current at smaller capacity, that is, with fewer plates in the package. AGM batteries appeared on conventional cars more than ten years ago. Currently, AGM car starter batteries are used as a power source for the “Start-Stop” system, which is equipped with a number of car models from leading manufacturers due to the ability to quickly give and receive large amounts of energy, the ability to painlessly withstand deep discharges (with periodic discharges more 50% AGM - the battery will last four times longer than a regular one) and will not degrade with frequent discharge-charge cycles. After all, fiberglass mats, in addition to everything, mechanically hold the active mass on the plates, preventing it from crumbling. That is why, on cars with a Start-Stop system, such a battery can last four to five years, and not two to three years, like a regular “liquid” one.

Serviceable and maintenance-free battery. What to choose?

A battery stores and stores energy that can be used as electricity. It is impossible to bring a car without it. If this element fails, it most often needs to be replaced. Charging only helps to delay the purchase of a new device for a short time, and here car owners have a question - what type of battery to choose?

Serviceable battery

The battery has this name because you can actually unscrew the caps from the cans and see what is inside, as well as check the level and condition of the electrolyte, density, condition of the lead plates, the presence of sulfate crystals, boiling during charging. This is quite a significant plus - you can control the battery and make the right decision in a timely manner.

Maintenance free battery

This battery does not require maintenance. The device does not have unscrewable plugs - you won’t be able to see its “insides”. This is a sealed design with six jars, each containing a plate and filled with electrolyte - all of them are in a completely sealed space. When heated and then boiled, the electrochemical liquid rises in the form of steam. However, it does not come out of the sealed housing, but condenses on the walls and falls back down.

There are several different battery technologies of this type, for example:

with liquid electrolyte - have sealed holes into which distilled water is added;
gel - with thickened, dried silica gel, permeated with microcracks that do not allow electrolyte evaporation to evaporate;
AGM – with absorbed electrolyte, almost no gas emissions during operation, developing high discharge currents and requiring no maintenance during the entire service life;
EFB - improved acid batteries with a thin layer of hygroscopic fiber applied to the positive plate, which prevents the active mass from shedding.

Which is better?

It is quite difficult to give a definite answer about which battery is better. The peace and safety of not only the car, but also the nervous system of its owner depends on the correct choice. When studying the store’s assortment, you need to clearly understand what you expect from a new device, and also know what specific battery characteristics are needed in your particular case.

One of the obvious advantages of maintenance-free batteries is that they do not require constant checking and monitoring. In such models, the electrolyte boils away significantly less than in service models. They also have a longer lifespan and produce more inrush current when starting the vehicle.

The advantages of batteries that do not require maintenance include their low degree of self-discharge. Any battery will discharge when stored for a long time. However, these batteries lose only up to 2% of their charge monthly, while serviced batteries lose up to 20% of their charge over the same period of time. Therefore, installing the former eliminates the possibility that the car will suddenly become unusable due to a frozen or discharged battery.

The charging process for this battery has one important feature, which should be taken into account when purchasing it. This requires using only a special charger, which eliminates manual adjustment of the current power. Application conventional device is fraught with squeezing out boiling electrolyte from the battery if the current through the emergency valve is incorrectly set. Subsequently, this affects the density of the liquid in the battery and reduces its service life.

Despite all the advantages of maintenance-free batteries, the production of maintenance-free batteries has not yet ceased. The fairly high demand for them is largely due to their low price compared to models without maintenance. Also, high-quality operation of maintenance-free batteries requires good automotive electrics, which is difficult to achieve, for example, in cars domestic production. Short-circuiting or overcharging is not allowed; the device must be charged at a constant, even voltage, without surges, in a strict range: from 13.9 to 14.4 Volts. When discharged, you cannot use a conventional charger - to replenish the energy of such a battery, a special charger is required that holds D.C. on the terminals.

Battery maintenance is necessary if, as a result of use, the performance characteristics of the battery have decreased (the starter turns too slowly, the car does not start, etc.). The main reason is the deviation of the battery from operating parameters. Service includes:

adding distilled water (electrolyte);
cleaning the body from white deposits and dirt;
recharging with a charger.

High-quality battery maintenance reduces the likelihood of its rapid failure and increases the reliability of engine starting in the cold season.

Thus, there is no definite answer which battery is better - each type of device has its own disadvantages and advantages. For car enthusiasts, owners of new vehicles with modern electronics, the best option are maintenance-free products, and experienced car owners serviced models can also be selected.

Whatever device you prefer, you should purchase it only from reliable auto stores that provide receipts and warranty cards. This will save you from the high costs of repairing or replacing the battery if it breaks down: expertise in service center will identify a manufacturing defect and will be the basis for a free battery replacement.