There is an opinion among motorists that a battery can only be installed in a car with the capacity recommended by the instructions, since with a lower amperage it will boil, and with a higher amperage it will constantly be in an undercharged state. But in fact this is a deep misconception, let's think about why.
A little theory.
Without delving into various technical terms, a car network can be imagined as a chain of interconnected elements: battery - generator - starter - on-board system. The latter, in the absence of additional energy-intensive equipment, consumes little energy, however, like the starter, which acts as a consumer only when the engine starts (the rest of the time it does not work). What remains is the “battery – generator” connection.
The first one provides electricity to start the engine and supplies it to all additional electrical consumers (radio, headlights, interior lighting, alarm, etc.) while the car is not started.
The second one replenishes the current losses of the first one (recharges it) and ensures constant maintenance of energy in the car system. This system has its own characteristics, similar and interrelated with the characteristics of the battery - voltage and power. The standard voltage of the on-board network practically does not change, it is equal to the difference between the voltage of the network and the battery and is in the range of 13.8-14.2 V. But the power is identified with the power of the generator, which can be different (both 40 A and 80 A). In this case, it is not at all necessary that these characteristics of the named device and the battery be equal. These figures are only information from the manufacturer about their bandwidth: how much electricity they can give/consume in 1 hour. In general, the charging current car battery is always less than what the generator is capable of producing, so the answer to the question of whether it is possible to install a larger capacity battery in a car is unequivocal: yes, it is possible!
What's the point?
In other words, if you put a more powerful battery under the hood of the car, but with the same voltage, it will simply take longer to charge and discharge, which will guarantee the maximum number of cold starts in cold weather.
For those who don't understand.
For those who still don’t understand anything, let’s explain with an abstract example. You have 2 barrels: 55 and 65 liters. You have the opportunity to supply the entire required volume in 1 second, but you don’t do this, because, firstly, you simply don’t need it so quickly, and, secondly, this can lead to the rupture of these same barrels, so water is decided supply through hoses with the same pressure. The smaller barrel will naturally fill faster, the larger one will fill more slowly. But the latter will last longer, because there is more liquid in it. It’s the same in a car, only instead of a barrel there’s a battery, instead of water - electricity, and instead of displacement - capacity, measured in A/hours. Hence it turns out that with the same power (and today almost all cars have the same current), one battery is more likely to replenish its charge than the second. That's the difference.
Are there any restrictions?
Surely, no one needs to explain that there should be a measure for everything. Battery capacity is no exception, so if you install a larger battery, then do it without “fanaticism”, because:
- a device that is too large may simply not fit into the space allocated for it in the engine compartment;
- the greater the difference, the greater the risk of overload.
By the way, do not rush to write off a standard-capacity device, since manufacturers always provide for a sufficient supply in order to:
- maintain the on-board voltage at a negative balance;
- have a reserve of starting properties even in the presence of all kinds of complicating circumstances;
- guarantee sufficient service life;
- provide the opportunity to get to the parking/repair site after the power source fails;
- power all devices with the engine off.
So before you experiment, think it through carefully. And our advice to you: if your car does not have powerful electrical consumers installed when the engine is turned off (system heating, powerful audio system, etc.), use what the manufacturer recommends!
Several opinions from car owners.
Igor:
“Be that as it may, you should never forget about the nature of the trips you make. If you only move around the city and often get stuck in traffic jams, it is better not to install a high-amperage battery, since it will indeed always be in an undercharged state.”
Sergey:
“It seems to me that everything is even simpler: when the engine starts, the battery loses the nth part of its charge, regardless of what capacity it has (55, 70 A/h, etc.), and how quickly the battery The “loss” will be restored depends not on the capacity of this battery, but on the power of the generator and the voltage of the on-board network.”
Egor:
“Don’t forget that a drive that exceeds the standard one in throughput will have less resistance (compared to the standard one) when fully charged, and more resistance when fully discharged. Hence, if there is a certain charge, everything will be ok, but if there is a deep discharge, and in the on-board network vehicle There is no energy reserve and no current limiter; installing a device with increased capacity is fraught with overheating of the network.”
There is always an opinion that if a car is equipped with a 63A/h battery according to the manual, then if you put 55Ah, it will boil, and if it is 90A/h, it will not be charged enough. In both cases it is assumed that it will fail within a short time. To our joy this is not the case. Let's think about it.
The vehicle's on-board power supply network, when the engine is running, is a device referred to in radio electronics as a “voltage generator” (with some stretch this is true). Those. Regardless of the current consumed by the equipment, it maintains a stable voltage in the network. Then we claim that the voltage supplied to the battery is always constant (like 13.8-14.2 volts). And according to Ohm's law (some people learn it at school), the current in a circuit is determined by the ratio of voltage to circuit resistance.
The voltage in our case is the difference (on-board voltage minus battery voltage). The battery resistance is almost constant, i.e. The charging current is determined by the battery's own voltage.
Now we finally start the engine. When starting, the battery loses a certain amount of energy and the voltage at its terminals decreases. The above voltage difference increases and the charging current increases. But you need to understand that the current that the battery takes into itself is determined by the state of the battery itself, and not the car’s electrical system.
A little about the current values. Once upon a time I measured the charge current on a VAZ-2106. So, in the first 0-15 seconds after starting, the current in the battery rose to 5-10 amperes, then within a couple of minutes it dropped to 0.5 amperes. On an engine that had been running for an hour or two, this current was 0.1-0.4 Amperes. Apparently this is a certain leakage current during charging, which, by the way, indicates that the battery is not 100% efficient. Although that battery was about 3 years old, plus it was domestic. But the main thing here is to understand that the average charge current does not go beyond 1-2 amperes.
Now about generators. The current value on them only indicates the maximum current that they can provide, but this does not mean that they always provide it. They always provide the current that consumers require.
AND NOW CONCLUSIONS: In the case when the battery “requests” 1-2 Amperes from the generator, both a 35A generator and a 200A generator will provide them equally well. Therefore, if you want, install any battery on any car. Everything will be charged. The main thing is that the voltage of the battery and the on-board network is the same.
Although in fairness I will say that you can choose a pair of car batteries in which the battery will not be fully charged. This is a pair in which the average charging current of the battery will be greater than the maximum current of the generator. But this does not apply to us, because... I showed you that the average battery charge current is several times less than the current of even one low-beam headlight lamp. So the battery will only be undercharged in a car whose generator cannot run even one headlight. Or in other words, the battery is such a small consumer in automotive electrical systems, probably smaller only than the clock in the dashboard.
And now for the funny unscientific evidence. Let us assume that the fact of overcharging and undercharging takes place. Then:
1. Imagine a fence in a field. On one side of the fence there is a huge ZIL (truck) and a small OKA. 2 pairs of holes were drilled into the fence and two pairs of wires were inserted into them. One pair comes from the truck's on-board network, the second from the OKI on-board network. The engines of both cars are running and spinning their generators. Being on the other side of the fence, we do not see which pair comes from, but with the tester we see 13.8 volts on each pair. We connect to each pair an identical battery designed for OCU. Now, if we claim that the one connected to the truck will be recharged, then how will this battery “determine” that it is connected specifically to the truck? After all, in both cases there will be the same voltage and the same charge current. Funny, isn't it?
2. Let's develop the situation to the point of absurdity. We have two cities. One is powered by a 1 GW power plant and the other by 1000 GW. In one city, Masha plugs her iron into the socket at home, and in another, Kolya turns on his iron. Question: which of them will burn out the iron right away? Probably Kolya, because his power plant is 1000 times more powerful! Does it make you even funnier?
Thus, we have proven that the consumer current is determined by the consumer itself at a constant supply voltage and does not depend on the generator.
So when choosing a battery, there is a simple rule - the battery capacity can be any, provided that it provides the necessary starting current to the starter. But no less. More? Yes, please, just stop on time, otherwise the battery won’t fit in the trunk. By the way, where it’s cold, it makes sense to install a more powerful battery, because It is known that as the temperature decreases, the actual capacity of the battery decreases.
More about the balance of battery capacity/generator current.
Question: “I put a 120 Ah battery on a Zhiguli instead of 55 and will it be recharged to its 120? This is recharging, not charging. This is the current limit."
Since the question is asked quite often, I considered it necessary to put THIS in the title of this conf. So, the answer: This is the most typical misconception this season (like the letters ZZZ - galvanizing the body on a VW).
The fact is that there is a misunderstanding of the processes of discharging/charging batteries. In order.
When starting the engine, some energy is wasted. Almost the same, regardless of battery capacity.
For example, 0.5 ampere-hour (less realistic). The starter is “absolutely unaware” of how many ampere-hours there are in the battery - he is “interested” only in what he needs. Well, it’s like “it doesn’t matter whether the depth is 3 meters or 3 kilometers - you sink the same way.”
The engine started and the generator started working. So, for the generator it is also deep purple how many ampere-hours there are in the battery - it is only “interested” in the VOLTAGE in the on-board network. And the downward deviation of the battery voltage relative to the “usual generator”. And the battery begins to “eat” energy. And he eats not incomprehensibly how much, but exactly as much (battery efficiency is almost 100%) as he lost when starting the engine. Those. the same 0.5 ampere-hour. And he eats at such a pace as the balance of power inflow/output of electricity allows.
One can imagine such an analogy.
There are 2 buckets of water - 10 liters and 5 liters.
The housewife sometimes needs a liter - then she tops it up. So what difference does it make - how much water is in the bucket?
Is the owner interested in the water level? (battery voltage) Then the water level at low tide of one liter will decrease not depending on its quantity, but on the DIAMETER OF THE BUCKET (starting current of the battery)! But it can be made different! You can have a wide, shallow bucket (high discharge current with low capacity), or you can have a narrow and high one (large capacity, but low current - these are 60Ah 180A batteries, by the way). And the large capacity of real batteries (an order of magnitude more than required) is needed mainly so that the starting current is greater. The bucket can be made of any shape, but the battery cannot be made “wide and shallow” - these characteristics are really strongly connected and you can achieve “width” only by making it “depth”.
Yes, there are still people who believe that if under water tap Instead of a bucket, put a barrel, then the tap will not withstand such a container and will break...
Bottom line - you can install at least a 500A/h battery - a 55-amp generator will cope with it. Just a question - is that much necessary?
When charging a completely empty battery with the same current, for example 1A, after 50 hours the 50th will already boil and the 80th will still remain undercharged. And after 80 hours, the 80th will also boil, and the 50th will boil for 30 hours. And when charged with a different current of 10% of the capacity of each, they will boil simultaneously after 10 hours. Therefore, when charging, the current is selected not in amperes, but as a percentage of the capacity. And the purpose of the generator is not actually charging the battery, but recharging - returning what was “borrowed”, for example, to start the engine or after landing with music or headlights. And the car should initially have a fully charged battery of any capacity. That is, if, when starting the engine, the 50th battery uses up 1% of its capacity, the 80th only 0.625%, therefore they will be recharged back at the same time by the generator. But a “loan” of eighty will still give more.
The car is equipped with a battery. And every car enthusiast has ever wondered what could happen if the car was equipped with a more powerful or weaker battery. Usually a person thinks about this when it comes time to change the battery. There are two myths. They are completely opposite to each other.
The first myth is smaller capacity
The first is that you cannot install a battery with a smaller capacity than what was installed by the manufacturer. Some people argue that if the battery is under rated, the alternator will overcharge and cause the battery to fail prematurely.
The car's generator is designed in such a way that it produces exactly the amount needed to charge the battery. The simplest example that exists in our lives. Found on the roads great amount cars in which the batteries have been installed for several years.
We all know that after a long period of use, the battery “loses” some of its power. Sometimes its actual power differs greatly from the nominal one, but this does not affect the operation of the generator in any way, and there are no situations associated with the battery boiling.
The only consequence of using a less powerful battery may be the inability to start the engine in cold weather. We know that at low temperatures, battery power can drop significantly.
If there are any in your region low temperatures, we do not recommend experimenting with replacing the battery with a less powerful option. Otherwise, one fine frosty morning, you simply will not be able to start your car.
Myth two - large capacity
Now let's look at the opposite point of view. She claims that it is impossible to install a more powerful battery. This can lead to premature generator failure. We have already said above that the generator produces exactly the amount of energy that is necessary for fully charged battery Again, a simple example from life. Surely everyone knows traffic police officers.
You can ask them about this issue. Inspector vehicles have a huge amount of additional equipment that consumes a lot of energy. These are light and sound signals, walkie-talkie and much more. Therefore, for more comfortable operation, these vehicles are equipped with additional batteries connected in one circuit. It is unlikely that any of them will tell you that they encountered a situation where the batteries were not charged.
From all that has been said, it follows that there is nothing in installing a high-capacity battery that could negatively affect the performance of your car. There is even a small plus here.
You will not have any questions if you accidentally leave the car and forget to turn off the lights, or if you listen to music for a long time at a picnic or other place. Moreover, in winter time, you can safely start your car. Car enthusiasts with low-power batteries will not be able to do this.
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 different batteries on cars during assembly, but the power of the generator remains unchanged. A simple conclusion follows from this that the battery capacity weakly depends on the power of the generator. The main thing you should consider if you decide to purchase new battery, this is the starter power. Because there are quite frequent cases when, due to too much battery power, the generator failed, because it was not designed for such overloads.
If you turn to experts and bombard them with questions, you will get a clear answer about exactly when 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 the battery charge is catastrophically lacking even when the engine is running, you should not immediately rush to look for a more powerful battery and shove it 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. She'll 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
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. Usually the voltage in the on-board network is 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 true 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 short video, let's look.
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