How to choose a battery for a car

2024 Author: Malcolm Clapton | [email protected]. Last modified: 2023-12-17 03:44

Everything you need to pay attention to when buying.

1. Capacity

One of the key parameters of any battery, which is measured in ampere-hours (Ah, Ah). On passenger cars, depending on the volume and type of engine, the capacity of the battery can be from 45 to 66 Ah. The most common are batteries with a capacity of 60 Ah - they are installed on most cars with gasoline engines with a volume of 1, 3 to 1, 9 liters.

The capacity of batteries for diesels and SUVs with a large engine capacity can reach 75 and even 90 Ah.

Capacity refers to the available supply of energy. In other words, how many times in a row you can crank the engine frozen in frost with the starter.

In theory, it is possible to install a battery with a larger capacity in a car and get an advantage, but in practice it is not so simple. First, the battery may not be fully charged from a standard generator. Secondly, due to the large dimensions, there is not always a place for the battery.

Therefore, it is still better to adhere to the manufacturer's recommendations and use batteries with a nominal capacity. You can find out which one in the car manual or by checking the label on the old battery.

2. Starting current

Another fundamental characteristic that plays an even greater role than capacity. Indicates the maximum amount of current that the battery can deliver in a short period of time from 10 to 30 seconds at a temperature of –18 ° С. The starting current is always indicated on the label in amperes. The higher the value, the easier the engine starts.

There are three main standards for marking inrush current depending on the battery manufacturer and country of destination. In Russia and Europe, the EN classification is widespread, in Germany - DIN, and in the USA - SAE.

EN, DIN, SAE standards vary. Therefore, when comparing the indicators of two batteries, pay attention to the values.

The average starting current for cars with gasoline engines is about 255 A, for diesels - about 300 A.

If possible, it is better to buy a battery with a higher starting current. Such batteries are more expensive, but they are guaranteed to allow the engine to start even in severe frost.

3. Dimensions

Depending on the capacity and brand of the car, the dimensions of the batteries differ. In cars, two main standard sizes are most often used: European and Asian. The first ones are lower and longer, the second ones are higher and narrower.

The dimensions of a standard European 60 Ah battery are 242 × 175 × 190 mm. The Asian counterpart of the same capacity has a size of 232 × 173 × 225 mm.

The installation site is designed strictly for the dimensions of the battery, so it will not work to shove in a battery of a different size. The exception is cars that have several modifications on the same base. In this case, there may be free space.

In order not to miscalculate when buying, be sure to check the technical documentation for the car or measure the old battery. However, you can simply buy a battery of the same capacity as the old one: as a rule, within the same rating, the batteries have the same size.

4. Mounting type

In addition to dimensions, the type of attachment is important for installation. On European cars, the battery is secured using pressure plates that cling to the lugs at the bottom of the case. On Asian cars, there are no such sides, and the battery is pressed against the site with a frame or bar, which are attached to the top on hairpins.

Check which mount is used on your car and buy the appropriate type of battery. The service life of the battery will depend on the reliability of the fasteners, since the plates crumble from excessive vibration and shock and become unusable ahead of time.

5. Polarity

Another difference in the design of batteries is their polarity, or, in other words, the location of the electrodes. It can be direct and reverse. For batteries with straight polarity, the positive electrode is on the left, such are used on domestic cars. On foreign cars, batteries with reverse polarity are often used, in which the plus is located on the right.

You can find out what polarity the battery is on your car, as always, from the operating instructions or by carefully looking at the old battery. To do this, you need to turn it so that the electrodes are closer to you, and determine the location of the positive terminal.

6. Serviceability

Low-maintenance and maintenance-free batteries are now available on the market. As the name implies, the former require some care and control, while the latter do not require any outside intervention throughout the entire period of operation.

Low-maintenance batteries are more affordable. From time to time, it is necessary to check the level and density of the electrolyte in them, adding distilled water if necessary. This is done through plugs on the top cover, which can sometimes be hidden under a small removable panel.

Maintenance-free batteries are self-sufficient and do not require attention. They are less susceptible to the boil-off of the electrolyte, so you don't need to add something to them. To check the state of charge, a special peephole is used, signaling the need for recharging. There are no other additional elements on the battery cover.

7. Appearance

Before buying, you need to make sure that there are no chips, cracks and other damage on the battery, as well as electrolyte leaks. The battery electrodes should be free of scratches, distortions and marks from the installation of the terminals. Otherwise, there is a possibility that this is a used copy, which for some reason was returned to the store.

8. Date of manufacture

Many motorists try not to buy batteries that are more than a year old. And it is right. Battery life is measured from the moment the electrolyte is filled, not from the beginning of use. Therefore, it is better not to take batteries stale in the warehouse, even with a good discount.

You can find out the date of manufacture of the battery by the code stamped on the case. Manufacturers use different markings, information about which can be found on the official websites.

For example, consider how the release date is indicated on batteries of popular brands.

• "Aktech", "Beast", Duo Extra - a four-digit code XXXX, where the first two digits indicate the number of the month, and the last - the year. For example, 0918 is September 2018.
• Yamal, Batbear, Tyumenskiy Medved - six-digit code XXXXXX, in which the first two digits are the month, and the last four are the year of production. Let's say 072018 would mean July 2018.
• Titan, Cobat - five-digit code XXXXX. The second and third digits show the week of production, and the fourth character is the year in the form of a Latin letter (S - 2017, T - 2018, X - 2019). Code 135T2 reads end of August (35th week) 2018.
• Bosch, Varta - indicates the first character of the four-digit FIFO code for the year and month. The value can be determined by. September 2018 corresponds to the letter Q, October to R, November to S, and so on in alphabetical order.

9. Brand and store

Lesser-known manufacturers bribe with an affordable price, already established brands like Varta and Bosch justify the high price with quality and reliability.

Which manufacturer to choose is up to you, but it is better to buy a battery in a specialized store. In this case, you can be sure of the originality of the product and the warranty provided.

10. Checking upon purchase

Before you buy a battery, you need to check it using a load plug or a special tester, which are always at hand in a good store.

The voltage of the so-called open circuit, that is, without connecting the load, should be in the range of 12, 5–12, 7 V. A charge level below 12, 5 V indicates that the battery needs to be recharged. But if possible, it is better to take another copy.

When connecting a load of 150-180 Ah for 10 seconds, the voltage should not fall below 11 V. It is also better to refuse to buy a battery that does not withstand these parameters.

Useful Tips

And finally, a few recommendations that will simplify the purchase and help the new battery last as long as possible.

• Do not rush to throw away the old battery removed from the car. Take it to the store and get an extra discount on a new one.
• Ask a technician to check the charging relay of your car and make sure that it delivers the required voltage. Usually within 13, 8-14, 5 V.
• After purchasing the battery, do not be too lazy to recharge it with a small current for 2-3 hours.
• Do not completely discharge the battery to prolong its life.
• Monitor the charge level. If you are traveling short or short distances, charge the battery once a month using the wall charger.
• Watch the terminals and clean them of oxides, which deteriorate contact and can cause the battery to undercharge.