Every day we start the car and do not even think about how it happens. In order for the engine to start its work, a whole complex of systems and mechanisms is used. One of the most important in this chain is the battery. Without it, it is impossible to start the engine. Over the years, the battery loses its capacity. The car starts to run worse. Also, often the owners have a problem of lack of charge. Why is the battery not holding a charge? Find out in our article today.
When to sound the alarm?
At what voltage can it be argued that the battery does not hold a charge? The minimum value to start the motor is 12.5 volts.
In this case, the motor will resume operation at the first turn of the key. If this figure is less than 0.5 volts, the motor will also start, but with great difficulty. A voltage of 11 volts or less is considered critical. In this case, there is a risk that the engine will not start at all. How long does the battery hold a charge? Ideally, it should maintain a stable value without rechargingup to three years (but subject to regular use of the car, as it charges the battery with a generator). If, after arriving home in the evening, the battery runs out the next morning, this means that the battery is faulty. In case of downtime, it should last at least one month.
Tranquil reasons
You need to start looking for a problem small. Visually inspect the contacts that go to the battery. Terminals must be free of oxidation. If they are present, it is difficult to start the engine both hot and cold. The reason is simple - the terminals do not fit tightly to the battery terminals. Accordingly, less starting current goes to the starter.
And after starting the battery cannot be fully charged from the generator due to the same oxidation. As a result, the battery does not hold a charge well, and the car is difficult to start. Another commonplace reason is damaged fuses on the generator. They are metal and are in a separate block. If these plates are burned out, the charge will not go to the battery. As a result, all electrical appliances will take energy from the battery, and it will not be replenished. The solution to the problem is to replace the fuse.
Banks
This is a more serious reason. Banks are the same six holes that are in the battery. Each jar contains lead plates. The latter are placed in an acidic electrolyte. In the process of contact between the plates and the electrolyte, electricity is accumulated, which is later used to start and operate the car. The voltage in each bank is approximately 2 volts. And if one of the canswill not work, the battery will only charge up to 10 volts.
These elements become unusable for two reasons. This is:
- Evaporation of the electrolyte. How to define it? When you unscrew the cap, you will notice a low fluid level. In a certain bank, it will be less than in others. But it also happens that liquid evaporates in several compartments at once.
- Shedding plate. In such a situation, the electrolyte level may be normal. But the liquid itself is not transparent, but black (almost black) in color.
And if in the first case you can still try to solve the problem by adding distilled water, then when the plates are deformed, the only way out is to buy a new battery. Note that the battery capacity will not drop after adding distilled water. In jars, it is she who evaporates, not acid. The latter is much heavier and stays on the plates.
Closure of plates
Incorrect operation may cause this phenomenon. This happens if the battery often goes to zero. It could also be electrolyte freezing. But this happens if the car often stands in the cold over 30 degrees. In order to prevent freezing of the plates, it is recommended to keep the battery warm in severe frosts, that is, bring it into the house with you.
Battery not holding a charge: plate recovery
Some try to restore such a battery by long-term charging with low current. But it won't do anything. This battery is restored as follows. Produce firstwashing jars with distilled water. It fills the compartment to the maximum. Then they mix (in this case it is possible and even necessary to turn the battery upside down) and drain. If necessary, repeat the procedure again until clean water comes out of the holes, without dirt and a dark shade. In some cases, it is possible in this way to clean the plates from oxidized particles and return life to the old battery. But if there is too much dirt, such plates may no longer take a charge even after 10 washes.
Desulfation
If the battery does not hold a charge, s alt deposits may have occurred on the plates. They need to be removed. To do this, we purchase a special desulfatizing additive to the electrolyte in the store.
Also, the removal of s alts can be done using a special memory. The desulfation procedure is carried out in several steps:
- First, the purchased additive is dissolved in a fresh electrolyte (its density must be at least 1.28 grams per cubic centimeter). It takes quite a long time - 48 hours.
- Next, electrolyte is poured into the jars. You should check its density. This is done using a hydrometer. This parameter must be at least 1.28 grams.
After that, the plastic caps in the cans are unscrewed and the charger is connected to the battery. In order for the battery to hold a charge for a long time again, you need to make several charge-discharge cycles. On the memory you need to set the minimumcurrent strength. It should be no more than one tenth of the maximum. When the battery voltage reaches 13.8 volts, the charge current should be halved. Next, we measure the density with a hydrometer. Leave the battery for two hours. Then we take measurements again. If the density has not dropped, then we have managed to restore the dead battery
But that's not all. We need to make an electrolyte adjustment. To do this, bring it to a density of 1.28, and then add distilled water. After that, the battery is discharged. A powerful lamp or resistor is connected to it and the current is limited to one ampere. You need to wait until the voltage drops to 10.2 volts. From the moment the load is connected, the timer must be turned on. This is an important parameter during battery recovery.
The discharge time must be multiplied by the discharge current. So we get the battery capacity. If it is below the nominal, you will have to repeat the charge-discharge cycle. And so on until the capacity matches the factory one.
