Who installed a 75 amp battery on a small car. What happens if you put a larger capacity battery in your car? What are the differences between batteries of different capacities? Let's show it with a practical example

Very often I receive letters on my website about car batteries. Especially, one of the most popular - is it possible to install a battery on a car with a larger capacity? THAT is, the capacity of your battery is, for example, 55 Ah (Ampere * hour), and you want to install a battery with a capacity of 70 Ah! What will happen and can it be done? Let's talk about it...

I’ll say right away that there are a lot of myths about this issue. For example - The car is equipped with a 60 Ah battery (according to the instructions), if you put it at 50 Ah, it will boil, and if you put it at 70 Ah, it will not be charged!

This is wrong! You can install both batteries on your car, nothing bad will happen, the most important thing is that they fit in the regular place of your car. After all, more capacious batteries are larger.

And now in more detail

Without going into deep technical details and saying in simple language(may the electricians forgive me), the car network has a certain relationship: battery – generator – starter – vehicle’s on-board network. The vehicle's on-board network consumes little energy (ideally) if there is no additional energy-intensive equipment. What remains is the generator - battery - starter. The starter consumes energy only when starting the engine (it does not work further), it should be noted that during one start passenger car“on average”, about 1 – 2 Amperes of energy from the battery are consumed (in cold weather it can be much more).

After, the generator must make up for the loss of battery current when starting the engine, that is, recharge the battery. Typically the voltage is on-board network about (13.8 - 14.2 Volts) it is almost constant, this is obtained from the voltage of the on-board network minus the voltage of the battery itself (which is almost constant).

The generator also has its own power characteristics - there are 40 A and 70 A and 80 A, etc., but this does not indicate what kind of battery this generator is designed for. This characteristic indicates the maximum current that the generator can produce per hour. But the current consumed by the battery (for recharging) is tens of times lower than what the generator produces.

What does this mean in practice?

If you install a battery with a larger capacity, but with the same voltage, it will simply take longer to charge, albeit not significantly, but longer! However, this means that it will take longer to discharge! This is especially important in cold weather; the current of the “larger” battery will be enough for a greater number of “cold” starts!

If at all on your fingers...

Imagine - there are two barrels of 55 liters and 70 liters (barrels are batteries). Both are equally filled with water with the same force (voltage in the car network), the barrels cannot be filled with water immediately (that is, supply 55 and 70 liters in one second, this is simply not realistic and can destroy the barrel, and this is not necessary), but need to be filled at a decent (uniform) water pressure so that the filling of the barrel is uniform (this uniform water pressure is uniform charging of the battery), then one barrel will fill faster than 55 liters, the other slower than 70 liters. But there will be more water in another barrel (70 liters) and it will last longer. What happens is that batteries are like barrels, only they are filled with energy, the capacity is measured in A/h, some have 55, some have 70, etc. With the same currents (and now almost all cars have the same current), one will fill with energy faster, and the other longer. THAT IS ALL THE DIFFERENCE!

In conclusion, I want to say that many people want to install a battery with a capacity that is not significantly larger, for example, a factory 55 Ah, but they want to install 60 or 63 Ah - guys, it’s okay, install it! This will not have any effect on the vehicle's on-board network, battery - generator or starter.

Now let's watch a short video.

That's all, read our AUTO SITE.

When purchasing a battery, many people have natural questions about whether it is worth choosing a battery, for example, with a reserve, a larger capacity? Or with higher charging currents? Many people dream of getting rid of the numerous problems that battery maintenance or some problems with it promise them at once. At the same time, there are also specific fears that if you install a more capacious battery on the car than is required according to the instructions for the car, then it will not be charged from the generator, and if with a smaller capacity, then it will boil. Under any such circumstances, the battery will fail much faster and stop working adequately.

Experts point out that this style of thinking has a mythological nature. The voltage generator, which makes up the car’s power network, regardless of how much current this on-board network consumes, maintains a stable constant voltage. Accordingly, the voltage that is output to the battery always has constant characteristics. In fact, the current that goes to charge the battery from the on-board network is determined only by the battery itself, and not by the generator or the state of the network.

When the car engine starts, part of the energy from the battery goes to the needs of the starter, and the voltage at its terminals drops. The voltage difference between the network and the battery increases and the charging current becomes stronger, but only until the voltage equalizes. In the first seconds after the engine was started, the current in the battery rose by five to ten amperes, and after some time it dropped to a stable half-ampere. If the engine ran for an hour or two, then the battery supply current dropped to 0.3 - 0.1 amperes. Many people believe that this is generally a type of leakage current due to the fact that the battery efficiency is far from 100%.

It is indicated on the generator maximum current, which it is capable of generating. However, he is not able to do this all the time. Moreover, the generator produces the current required by on-board consumers in the network, including the battery. Thus, any generator, no matter what power it develops, will give the battery exactly the amount of current that it “asks for”. A normal full charge will occur only to the amount for which the battery is designed, and no more. At the same time, you need to understand that the battery consumes a very small amount of current - it can be considered the smallest consumer of all.

Many motorists are of the opinion that a car battery must strictly comply with the stated standards - or problems will arise. Specifically: a battery with a lower capacity will boil during charging, a battery with a higher capacity will remain undercharged. The conclusion from this statement is that the battery life will be significantly reduced. Why is this statement false?

The principle of operation of the on-board power supply network

Each car has a power supply network, and it operates according to the following scheme: energy flows from the battery to car generator, starter and on-board network (equipment).

To operate the starter, energy is consumed only during the time when the engine starts. However, it is worth considering that a small percentage of the battery’s energy is spent on one start. In absolute numbers, this is no more than 2 Amperes out of the available 40 or more. True, in the cold season this figure increases.

The generator's job is to replenish the energy lost when starting the engine, that is, to charge the battery. As for the voltage in the power supply network, it is maintained at a relatively stable level (about 14 volts).

The current that is involved in the network is the ratio of the voltage to the resistance value. The first indicator is the difference between two values, the voltage in the on-board network minus and the battery. And the battery resistance is at a constant level.

When the engine starts running, the battery loses a certain percentage of its charge and the voltage at its terminals drops. This leads to the voltage difference described above. Also, the charging current increases.

If you analyze these indicators, it becomes clear that immediately after the engine starts, the current level increases to 10 Amperes, but then decreases many times. When the engine operates for a long time (more than an hour), the charge current level is limited to one ampere, the average value corresponds to several amperes.

Key Takeaway: The capacity of the battery used may vary.

The process of bringing the engine into working condition requires energy, which is almost always the same, regardless of the capacity figure. That is, for the generator this figure is not of fundamental importance. The voltage in the on-board network is important. The battery uses a small percentage of the power available from the generator. That is, you can safely choose a battery that has a large capacity. It will just take longer to charge it. But in this case, the battery discharge time increases. The main thing is that the voltage of the battery and on-board network do not change.

Therefore, when choosing a battery, you must follow the following rules: the capacity can be any - the main thing is that it provides the starting current that is necessary.

What are the differences between batteries of different capacities? Let's show it with a practical example

The current indicators are equal - this is typical for modern cars. A battery with a smaller capacity will be recharged faster than a battery with a larger one - that’s the only difference.

Let's say the car has a 55 Ah battery. Let's take two batteries with different indicators. The first is less than the base one - for example, at 50Ah. The second - at 70 Ah. Let's imagine that they were completely discharged. After 55 hours of charging with a current of 1 Ampere, the first battery will be fully charged and will begin to boil, the second at 70Ah will still need to be recharged. After 70 hours of charging, the second battery will also boil, and the first will be in a boiling state for already 15 hours. But you need to take into account the fact that the generator’s task is not to charge, but to recharge the battery to the required values. And the 1% of capacity consumed at startup is compensated in both cases in approximately the same time - no matter how different the capacity is.

What factors need to be taken into account

1. The power characteristics that distinguish a particular generator are confused by many with the indicators necessary when choosing a battery. But the characteristics indicate something else: the maximum current at which the generator will operate. But practice shows: when recharging a battery, it uses a small part of this power (tens of times less).

2. How much electrical equipment is installed on a particular machine. If there are no additional options, a small amount of energy is used for the on-board network. With energy-intensive equipment, these figures will naturally increase.

3. You need to take into account the dimensions (dimensions) - otherwise the battery simply may not fit or may not be fixed in the designated place.

4. Operating conditions. At low temperatures, it makes sense to choose a battery with a larger capacity.

So, in addition to a battery of the recommended capacity, your car will be perfectly suited to a battery with a slightly larger capacity, provided the other parameters are met. But you shouldn’t take a battery with a smaller capacity, as it will discharge faster in extreme conditions and may fail.

Many drivers are unhappy with the battery power in their cars. And in an attempt to get what they want, they often wonder whether it is possible to install a battery with a larger capacity on their iron horse. They believe that if you install a larger battery, you can increase the energy reserve. However. Is this really so and does it make sense to buy a more capacious unit?

Most manufacturers install them on cars during assembly different batteries, however, the generator power remains unchanged. A simple conclusion follows from this that the battery capacity weakly depends on the generator power. The main thing you need to consider if you do decide to purchase a new battery is the power of the starter. Because there are quite frequent cases when, due to too high power The battery failed and the generator failed because it was not designed for such overloads.

If you turn to experts and ask questions, you will get a clear answer about when exactly an overloaded generator can surprise the car owner and fail. There are many nuances and accompanying circumstances here, such as the degree of discharge of the battery, the features of the long-suffering generator itself, and the operating mode of the engine.

In order not to risk the health of their iron horse, many drivers prefer not to interfere and drive with a battery of the power that was provided and installed by the manufacturer. Because everything here has already been thought out and planned for you by specially trained people. During assembly, a battery of a certain capacity is installed in order to easily perform such tasks as operating the car’s electrical appliances when the engine is turned off, optimal service life, and also providing a small reserve of energy for the operation of the car in case the generator stops working.

If you begin to notice that there is a catastrophic lack of battery charge even when the engine is running, you should not immediately rush to look for more powerful battery and shove him into the car. It is best to replace it with a similar one or recharge it using a special device.

A reasonable solution would be to install a larger battery if the car has a very powerful audio system. It will need more energy, and the choice in favor of a “stronger” battery will be quite logical.

And in other cases, finding an exact answer to the question of whether it is worth replacing a familiar battery with a more powerful unit is, unfortunately, quite difficult. However, it is worth taking into account the words of car manufacturers, who do not recommend carrying out such fraud.

Photos from Internet resources

Many car enthusiasts believe that a certain car should use batteries of a certain capacity and power. That is, the 190 battery must be replaced with similar ones, otherwise this may lead to accelerated failure of the product or problems in the operation of the on-board network. Is this true? Let's try to figure it out.

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The principle of operation of the on-board power supply network

As you know, every vehicle is equipped with an on-board network - a power supply system.

It functions according to the following scheme:

• voltage from the battery is supplied to the generator unit;
• then it goes to the starter device;
• and after that it is transferred to the electrical equipment of the car.

To start the starter unit, a short-term voltage supply is required; this is only necessary when starting the engine. For one such start, the battery spends a small percentage of energy - usually about two amperes out of 40 or more, but in winter this value increases.

The purpose of the generator unit is to replenish the energy lost by the battery when starting the power unit. Essentially, this unit charges the battery while driving. In general, the mains voltage vehicle varies around 14 volts, as a rule, it is stable. The current used in the electrical network is the ratio of the voltage to the resistance parameter.

When the driver starts power unit car, the battery loses a minimum percentage of charge, that is, the voltage at its terminals decreases. As a result, this contributes to the voltage difference that we have already mentioned. If we analyze these values ​​more carefully, it becomes clear that immediately after the motor starts, the current indicator will increase to 10 amperes, and after that it will decrease many times. If the motor runs for a long time - more than one hour - the battery charge value is limited to approximately 1 ampere (video author - transistor815).

What are the differences between batteries of different capacities?

Now let's move on to the main question - is it possible to install batteries of different capacities on a car, for example, instead of using a 70 A/h battery, install a 100 A/h device? And most importantly, will it make sense?

As is known, the generator unit has its own technical characteristics in terms of power - at modern cars generators of 40 A, 70 A, etc. are used. However, this does not indicate that the generator unit is intended for use with rechargeable batteries appropriate power. This indicator indicates the maximum current value that the node can supply in one hour of operation. In turn, the current consumed by the battery can be tens of times less than what the generator unit can produce.

For example, if you decide to install a 100Ah battery instead of using a 55Ah, 60Ah or 70Ah battery, but the voltage is the same, then the only difference will be that the device will take longer for charging. But you need to take into account that this also means that the product will take longer to discharge, which is especially important for our compatriots in the cold season. Thanks to this, the driver will have more cold start attempts (video author - Yuri Krym).

Another example that will allow you to fully understand this issue. Imagine two containers - one for 60 liters and the other for 100, in this context the containers are batteries. These tanks are equally filled with liquid, which enters them under the same pressure (in this case, this means the voltage in the on-board network of the machine). The tanks cannot be filled with liquid instantly, because if 60 and 100 liters are supplied in one second, this will simply lead to the destruction of the tank. They must be filled under a decent pressure of liquid so that the filling of the tank is uniform, in particular, in this case we are talking about uniform charging of the battery.

Accordingly, a tank with a capacity of 60 liters will fill faster than one designed for 100 liters. However, in the second case, there will be more liquid in the reservoir and, accordingly, it will last for a longer time. With batteries too - some are designed for 60 A/h, others - 100 A/h, others - 190 A/h, etc. The only difference between batteries is that it will take longer to charge a device with a higher capacity than a device with a lower capacity.

There are no other differences between the products. That is, if you decide to even slightly exceed the capacity of the product by installing a 60-65 A/h device instead of a standard 55 A/h AAB, then there is nothing wrong with that.

Photo gallery "Damage"

What factors need to be taken into account?

Other things to consider:

1. The power values ​​specific to a particular generator unit should not be confused with the parameters used to select a product. However, this value may indicate something else - the maximum current parameter at which the generator unit will operate. In fact, during charging, the product uses a minimal part of this power.
2. You should also take into account the load on the car’s electrical network, that is, how much additional devices and devices installed on a specific car. In the event that additional gadgets such as music amplifiers and subwoofers, DVRs, chargers for smartphones, GPS navigators, no, then less energy will be used for the electrical network. If you use energy-intensive electrical equipment, then the load parameter will be increased accordingly.
3. You should also consider the size of the product you are purchasing. If the dimensions do not match, then you simply will not be able to install the device in the seat.
4. An equally important point is the terms of use. In severe frosts, of course, it is better to use a product with a higher capacity.

If you install a larger capacity battery on a car, it will not be recharged, because the generator will not produce the current it needs, thereby quickly becoming unusable, just like the generator, which will work at the limit of its capabilities.

Price issue

The cost of a product depends on many factors - the type of product, its manufacturer, as well as technical specifications device The cost of inexpensive batteries today is about two to three thousand rubles. Products medium price category cost approximately 4-8 thousand rubles. More expensive options- from 9 thousand and above.