There are several reasons why the car battery is completely discharged.
Firstly, this happens if the energy consumers installed in the vehicle have been operating for a long time with the engine turned off.
The second cause of discharge may be a circuit that has passed through a contact to the housing.
Thirdly, the voltage indicator is less than 13.8 V under the condition of operation of faulty electrical equipment.
The fourth reason is due to the negligence of the owner of the car, when in the vehicle it is allowed to use sources of energy consumption that are not provided by the manufacturer.
Another reason often is the parking of the car for a long time (at least 20 days), if the negative cable was not disconnected or if the battery was stored for a long time without recharging.
Charging a car’s battery can be done in several ways, each of which is endowed with a special technical specificity. Before proceeding to their consideration, it is worth paying attention to the fact that car batteries have several features. They relate to:
- inconstancy of internal resistance arising in the process of charge;
- the dependence of the charge quality on temperature and current strength;
- change of various processes occurring inside the battery during the charge process.
So, charging a car battery starts with connecting a charger. At the initial stage of the process, a relatively high indicator of electric current will arise, this happens due to the fact that the device has so far a small internal resistance. This indicator will gradually decrease as electricity begins to accumulate in the battery. Simultaneously with the increase in charge, a decrease in the level of efficiency is noted, which drops from a mark of 95% at the beginning of the process to a level of 80% at its end. The energy that is lost at this time is spent on heating the electrolyte inside the battery.
Charging the car’s battery comes to an end when there is a so-called boil. This is nothing more than gas evolution during electrolysis. The current indicator of a charged battery is considered normal if it is a tenth of its total capacity.
Charge the car battery with direct current.
From the name it is clear that this method involves supplying a constant current to the battery with a value that does not change during the entire process. This procedure can be carried out in various ways, for example, using a rheostat, transistor circuits, adjusting the input voltage automatically or manually.
The advantage of this method lies in the possibility of establishing control over such a characteristic as the charging time of a car’s battery , which is possible due to the knowledge of its full volume and of the direct current value.
In practice, the process looks like this; a battery with a rate of 55 A / h needs to be infected within 10 hours. But after a 9-hour mark, you should lower the current to 2, 75 A and continue the process for another 2 hours. In this way, a decrease in battery heating and the amount of gas released during charging is achieved, which will positively affect the completeness of the charge and the battery life.
Faster car battery charging
This method is used when there is a need for fast charging of the battery, it is recommended to use it extremely rarely, because it negatively affects the overall battery life. The accelerated process allows a charge lasting half an hour to a mark of 70% of the total battery capacity. It is important to monitor the temperature of the battery and if the 450 mark is reached, the process should be stopped immediately.
As a result, I want to give a few recommendations for battery operation.
1. It is necessary to carry out full battery maintenance before the start of winter colds. If the car is not used in winter , you should not bring the battery into heat, it is better to leave it inside the car, after removing the terminals.
2. Do not leave a discharged battery in the cold, because the electrolyte with a low density will freeze, which will render the battery unusable.
3. Tipping the battery and, as a result, draining the electrolyte can lead to negative consequences. In this case, the plates are closed, which will also make it impossible to further use the battery.