⚖️ How to choose a battery or 15 steps to a successful battery purchase

The question - which battery to choose - with the modern variety of goods in car dealerships, seems difficult for many. Dozens of brands, different technologies and prices, advertising, sales reviews and more - all this complicates the task and confuses the car enthusiast. The purpose of this article is to break down all the important steps towards choosing a good battery for a particular car.

Step 1. Examine the old battery

For reasons unknown to the author, few people talk about this. But this step is on the surface. The question arose - how to choose the right battery? Look at the one that already turns the starter badly and buy a similar one. It also contains all the necessary parameters. What is not written can be measured. Elementary, right?

As a result, having studied the old battery, you can choose a new one, guided by criteria such as:

• Brand - if the existing one has shown its best side, then why not buy the same one.
• Capacity - written on the case. You can take it with the same one, or step aside for a few ampere-hours.
• Overall dimensions - per minute are measured by an old battery with a tape measure.
• The location of the terminals - which side is positive, and which side is negative.
• Terminal sizes - the difference between European and Asian standards is so obvious that you can do without a caliper.
• Rated voltage - if the car is a passenger car, then in most cases it is 12 volts.

Many other parameters can be found out from an obsolete battery, but they will not help much in choosing a new battery. These characteristics will have to be dealt with separately, which is done below. It is also not superfluous to consider the items presented in the list, since they have their own nuances.

Step 2. Battery manufacturer

Which battery to choose - Bosch or the unknown Sirukato? Do not rush to conclusions. After all, a manufacturer and a brand today are two different things. If you used to buy a battery of some well-known European brand, then there was a high probability that it was made in Europe. according to relevant standards. Now this probability tends to zero, since the lion's share of the market is littered with products of Asian industry. Do not forget about fakes, of which there are also many.

For these reasons, today there are more and more negative reviews about branded batteries. The man did not spare money, bought a battery of a famous brand, but he did not survive two winters. And all because the battery was made far, far from the brand's homeland, or even in some basement of our country. It follows that it is almost pointless to focus on the brand today.

A completely different situation is observed if we consider the choice of battery among domestic brands. They are in demand today for a reason. Inexpensive. Made according to some kind, but according to GOST. And very few people fake them. As a result, we have a lot of positive feedback about batteries made in our own country. And do not think that ours own technologies that are behind the times. Practice shows that, ceteris paribus, domestic batteries last much longer than Chinese or "European" ones made in the same place.

If, nevertheless, you want a European brand, then pay attention to the manufacturer. Sellers are required to honestly indicate it in the product description. Although they do it at the very end, and in a tiny font. In 90% of cases, it turns out to be far from Germany, or whatever you prefer there.

With brands, there is another trick that should help you choose a battery for a car. Do not be too lazy to look at the latest reviews of the brand you are targeting. Just for fresh. This is important, because what was done well five or ten years ago can easily turn out to be rubbish today.

Step 3. Dimensions of the selected battery

How to choose a battery by size? First you need to carefully look at the standard installation location under the hood. If it is limited to nearby parts and assemblies, it is clear that a large model simply will not fit. In addition to the "clean" dimensions on some machines, it is necessary to take into account the moment the battery is installed in its place. For example, in the author's car, the space around the battery is limited not only on the sides, but also on top. Accordingly, there is always a problem with choosing a battery in height, since it is not so easy to plug it in.

Does it make sense to choose a larger battery than it was before? Yes. In cases where you want to increase the reserve of ampere-hours. For the most part, it doesn't make much sense. But many are attracted by the idea of putting a larger capacity battery. As experience shows, 5-10 ampere-hours solve almost nothing. If you really need a larger margin in capacity, then it is better to think about installing a second battery.

Step 4. Polarity

There is direct and reverse. How to choose a battery according to this criterion, and why is it important? Let's start with the last one. If you accidentally (or due to a limited assortment) buy a battery with reverse polarity, and your car needs a direct one, it will be difficult to connect to the on-board network. Wires with clips simply will not reach the corresponding terminals.

The first thing that comes to mind in this situation is to turn the battery 180 degrees. But this almost always does not help, since the terminals on car batteries are not symmetrically located relative to the front and back sides. The second obvious way out of the situation is to increase the power wires. This is also often done, and it works. But the wires must be of a suitable section, and also do not forget about the insulation of the connections.

In order not to become a participant in the described dances with a tambourine, it is better to initially pay attention to the polarity and choose the right battery. Here is a short algorithm how it is done:

1. The front side of the battery is the one where the sticker with the information is located, and to which the terminals are closer.
2. If the positive terminal, when looking at the front side, is located on your left, this is a battery of direct polarity.
3. Accordingly, if the “plus” is on the right, this is a reverse polarity battery.
4. See which of the two options you have under the hood and base your choice on that.

Step 5. Diameter of battery terminals

12 volt car batteries are sold with terminals of two standards - European and Japanese. They differ in diameter. That is, if you choose the battery incorrectly, the clamps will either not fit on the terminals, or they will not be able to be tightened. Of course, you can always replace the clamps themselves. But this is again dancing with tambourines.

How to distinguish between European and Japanese standard terminals? For the first type, the terminal diameter is 19.5 mm and 17.5 mm for plus and minus, respectively. The Japanese have them noticeably thinner, namely 12.7 mm and 11.1 mm. They can also be distinguished by whether the terminals protrude beyond the dimensions of the case. They do not protrude from the “Europeans”, but from the “Japanese” they literally stick out from above. This rule does not always apply, but should be kept in mind as an additional guideline.

Step 6. Rated Voltage

Even the most inexperienced car enthusiast knows that most cars are equipped with 12-volt batteries. This figure is called the nominal voltage, and you should always pay attention to it when choosing a battery. This way you will avoid buying any 6-volt or 24-volt version. Such mistakes are usually not allowed, but you never know.

A more important parameter than the nominal voltage is the battery charge modes. So, for some batteries of the GEL type , a voltage of about 15 V is required, which many passenger cars do not have. Usually in the on-board network from 14 V to 14.8 V. This means that under certain circumstances, the battery you bought simply cannot be fully charged from the generator.

Step 7. Battery Capacity

A lot of myths have accumulated around this parameter. Some say that you need to choose a battery of exactly the same capacity as it was before. Others try to convey that a larger battery can cause alternator failure. Allegedly, he will not "pull" her. If you choose a battery of a smaller capacity, then there will be other problems.

Actually, it's all nonsense. The importance of capacity is often exaggerated. It is used by manufacturers and retailers to justify price increases. For car enthusiasts, this is another reason to boast, they say, I chose a battery for dofiga ampere-hours. If you do not want to bother with this issue, then just buy a battery of the same capacity as it was before.

If there is a desire or need to stick less or more ampere-hours under the hood, then here are some verified facts for you:

1. The generator will not burn out due to the fact that the battery will have a larger capacity. The only real difference is that it will take a little longer to charge.
2. In terms of autonomy, 60 A*h and 70 A*h are almost the same. It's like drinking 100 grams of vodka or 110 grams.
3. If you charge a new battery from a stationary charger, then additional capacity will require a couple of hours more time.
4. If you choose a battery of a smaller capacity, then there should be no problems with starting the engine because of this.
5. The same applies to cases where the engine is diesel. If the engine initially does not start well, then at least 500 Ah will have a battery, the chances of staying at home in the early winter morning will not decrease.

But if you are thinking about what battery capacity to choose with a limited budget, then knowing the above facts will help save a lot of money. After all, the more ampere-hours are written on the case, the more expensive the model. And vice versa.

Needless to say, the inscription is not always true. Practice and real measurements show an interesting picture. Some budget batteries with a declared capacity of 60 Ah do not even have 50 Ah. But those that have good reviews, often in a new condition are able to accumulate a little more than it is written. So the inscription on the sticker is all a filkin's diploma. There is no point in worrying too much about her.

Step 8. Inrush Current

Starting current is a very important criterion for choosing a battery, but you should not focus on it for a long time. And all because absolutely any modern battery, if it is a starter type, is capable of delivering starting current with a huge margin. Of course, if the marriage did not fall. If you don’t know how starter batteries differ from traction batteries, read the material at the link.

Let us briefly analyze the same current margin, which was mentioned above. On inexpensive batteries for cars with a declared capacity of 55-70 Ah, as a rule, a starting current of 500-700 A is indicated. To understand that this is an impressive reserve, you need to know how many amperes the starter needs to crank the engine. Let's estimate.

We know the voltage of the on-board network of a passenger car. On average, at the time of starting the engine, it is about 11-12 volts. For clarity, let's take a higher figure, that is, 12 V. Next, we need to find out the starter power that it consumes during operation. On machines with engines in the region of two liters, 1.5-kilowatt starters are installed. Plus minus.

Question: how many amps should the selected battery produce in order for the motor to start? Knowing the voltage and power, the current can be calculated using a simple formula:

I = P / U

Where I is the current in amperes, that is, in our case, the starting current of the battery.

P is the power expressed in watts.

U is the voltage in volts.

Let's convert one and a half kilowatts to watts, and we get:

I = 1500 / 12 = 125 A

That is, to start a two-liter gasoline engine, the battery must be able to give 125 A of starting current. It is for this reason that 500-700 A, written on the body of any modern battery, is a huge reserve.

Even if we take an engine with a large volume, diesel, take into account negative temperatures, then all the same, the figure calculated above will not come much closer to 500 A. This can only happen if the starter takes over. Then, of course, even a new battery with a starting current of 700 A will not always do its job.

Step 9. Battery serviceability

Which battery to choose - one that needs to be serviced, or one that does not require this? The first type is usually attributed to models that provide access to a liquid electrolyte (hydrometer vs refractometer). Accordingly , if the battery is without plugs, GEL or AGM , then it is maintenance-free. At first glance, maintenance-free batteries look more attractive. But this is only at first glance.

Firstly, even if the battery is of a maintenance-free type, it is still impossible to leave it unattended. Yes, there is no need to mess with the electrolyte, its level and density. But, at a minimum, it will be necessary to monitor the level of charge of the battery, the cleanliness of its case, and promptly clean the terminals from oxides and salts.

Secondly, with some skills, access to liquid electrolyte can significantly extend battery life. If you once encounter the fact that the battery boils when charging, you can practically do nothing - neither top up the electrolyte nor adjust its density. Also, you will not know if your battery has suffered from sulfation, because without barbaric disassembly it will not work to look at the plates.

In general, many experienced car enthusiasts do not recommend choosing a maintenance-free battery type. The only exceptions are those in which the electrolyte is not liquid, and access to it is absolutely not needed. That is, if you decide to choose between GEL and AGM , then skip this step.

Step 10. Engine displacement

Here the logic is simple, and familiar to many: the larger the engine, the more powerful the battery is needed. But, as we have already found out above, this is no longer about capacity, as they often say, but about starting current. Since modern batteries have the latter with a margin, it turns out that it does not matter which one to take for a particular engine. The way it is. Believe me.

Step 11. Motor Type

A slightly different, but similar picture with the type of engine. This is the second point regarding the selection of the battery according to the parameters of the car. The logic is this. If the engine is diesel, then the battery should be selected more powerful than for a gasoline of the same volume. Again, the success of starting the motor does not depend on the capacity in ampere-hours. Starting current, as a rule, with a margin. What then to focus on?

The most obvious answer is to look at the battery you want to replace. If there are no identification marks left on it, and you really want to “guess” by amperes, then choose as follows. For gasoline engines up to 3.5 liters, any model with a capacity from 55 Ah to 70 Ah is suitable. For example, on the same two-liter batteries, 60-65 A*h work fine. For diesels, you can throw in 5-10 Ah, if your wallet and space under the hood allow. But this is not necessary at all.

Step 12. Battery Technology

Which battery to choose - classic, calcium, gel, AGM, silver plated or another? By and large, the only difference that you will feel between all these types of batteries is their price. The rest is lyrics. The machine will work with any battery that is correctly selected for more important parameters than type.

But there are still some pitfalls here:

• If you decide to opt for a Ca/Ca type battery, get ready for the fact that it will not be able to charge up to 100% under the hood. He will have to periodically “help” with a stationary charger. Otherwise, sulfation.
• To buy a gel or AGM battery, immediately prepare a little more money than the classic costs. And also tune in to the fact that you will not see the benefits that the seller or manufacturer will tell you about in practice.
• AGM batteries "allow" themselves to be charged with high currents, which in theory can help save time. But you should keep in mind that any battery that is charged with huge currents loses its life faster.
• Today you can choose a good battery among such as Ca/Ca, Ca/Ag and other similar ones. But don't get too carried away. The additives that are indicated in the type name are actually not so many in batteries. This is a micron spread that slightly improves performance, but entails other problems.

In the end, it doesn't matter which type of battery you choose. Its service life largely depends not on technology, but on how you will operate it. For example, if you know whether you need to charge a new battery, then your chances of increasing the resource of the selected model increase.

Step 13. Date of release of the battery

The question - how to choose a car battery by release date - may seem silly to many. Buy the one that is "fresher", and that's it. But not everything is so simple. After all, the release date on the battery is not written in the form we are used to. Like food, for example. On batteries, it is knocked out directly on the case. Moreover, in the form of a code, it will not work to count the necessary numbers without preparation.

Therefore, remember the following 7 nuances regarding the release date of the battery:

1. You can check the release date when buying online only after you receive the goods in the mail.
2. If you are thinking of buying in a regular store, take a table with the decoding of the date by the code. They are freely available on the web.
3. Do not look at the release date if it is printed on a paper label. This is most likely a fake - an attempt to sell an old, stale battery.
4. Regardless of whether the battery was lying in a warehouse or standing under the hood, its adequate service life at the time of this writing is 5 years.
5. When choosing a battery in a live store, try to find out if the seller has serviced it. Information about this is in the article about why a new battery is discharged.
6. The warranty for a battery by law does not depend on what date was stamped on its case at the time of purchase. That is, if you were sold an old battery with a two-year warranty, then these two years begin to be counted not by the release date, but from the moment of purchase.
7. To choose a good battery according to this criterion, try to find an option that is no more than three months old from the date of issue. Older ones are not recommended for a number of reasons.

If at all there is time for a more thorough search, then a very competent decision would be to try to find a model that has been in the window for no more than a month. Although in practice there were cases when one and a half year batteries, properly serviced by the seller, served after purchase for the prescribed 5 years, and even longer.

Step 14. Cost

The price is simple. The first criterion is the available budget, under which the purchase is adjusted. The second - do not chase cheapness. What is sold at discounts or promotions is almost always of disgusting quality. Inadequately expensive batteries do not deserve the attention of the average car enthusiast at all. There is extra money - choose. But there will be zero sense from this, as they say. The best option is the one that costs 20-30% more than the cheapest available. Checked.

Step 15. Pre-Purchase Check

An elementary test of the battery with a load plug is the most important step towards a successful purchase. However, this is only possible if you decide to purchase a battery in a real store. On the Internet, no one will conduct such a test for you. The only thing you can do is to check the purchase upon receipt by mail, and refuse it if it was sent via the cash on delivery system. Although some self-respecting online stores issue both returns and exchanges without any problems, if there are adequate reasons for that.

Comprehensive battery check.

Brief summary

Since the article turned out to be large, we summarize all of the above for those who have mastered it completely. Before you finally decide which battery to choose, go through the following 15 simple steps:

1. Examine the old battery.
2. Do not confuse the concepts of brand and manufacturer.
3. If space for the battery is limited, pay attention to the dimensions of the purchase.
4. Don't forget polarity.
5. Terminal diameter.
6. Make sure the battery is not 6 or 24 volts.
7. Do not bother too much with the capacity if there is no way to check it.
8. Don't pay attention to starting current.
9. If the battery is with liquid electrolyte, then only serviced.
10. Engine size is not a benchmark.
11. For a diesel, it makes sense to take a larger battery.
12. If the battery technology is different from the classics, find out in advance about the complexities that await you.
13. Don't forget the release date.
14. Do not choose the cheapest or most expensive battery.
15. Check your purchase before paying.

And no matter which battery is chosen, do not forget about it after installation under the hood. Whatever it is, it needs regular attention. Cleanliness, recharge if necessary (master class of battery recharging with a photo report), exercise and so on. Only in this way will the purchase of the next battery be pushed back in time by at least five years.

VIDEO: about choosing a car battery