What is battery charging time? The degree of battery charge is judged by the density of the electrolyte. For maximum charge, the indicator is 1.26-1.28 g / cm³. In this case, the voltage can not be less than 12.5 V. It all depends on the initial indicator.
Important points
Battery charging time also depends on the time of year. For example, in summer, the lead-acid battery discharges more than half, and in the winter - only a quarter. Note that the additional battery needs that battery, in banks of which the density differs by more than 0.02 g / cm 3 .
The optimal indicator is the charging current of 0.1 of the maximum capacity. For a battery with a capacity of 55 A / h, this value is 5.5 A, and for 60 Ah - 6 A.
Charging Methods
The charging time of the car battery depends on the method selected. Currently using the following options:
- direct current;
- constant voltage.
Battery Discharge Stages
The charging time of the car battery is determined by the formula:
T = Q / I,
where Q is the total capacity of the battery, I is the magnitude of the charging current, A. Substituting your indicators in the original formula, you can determine the time period that will be needed to completely restore the lost capacity.
If you only need to partially restore the battery, the battery charging time is significantly reduced.
Important points
In order to roughly estimate the time spent on charging the battery with direct current, you first need to calculate the degree of battery discharging (in percent), then you can calculate the lost capacity by choosing the size of the charging current.
The calculation formula is presented in the photo.
About 40-50% is spent on efficiency, and the rest is spent on preheating, various electrochemical processes.
Application of the calculation formula
Charging should be accompanied by a periodic check of the process so as not to miss the moment the boil begins. If during 60 minutes the voltage at the battery terminals does not change during charging, therefore, the process is completed.
The parameters of the final voltage directly depend on temperature, charging current, battery resistance, alloy composition of the gratings, the presence of impurities in the electrolyte.
Number of cycles
Each subsequent recharging of the battery degrades its working life. At the same time, the time of fully charging the battery increases. It is determined by the formula:
Battery capacity / charging current * ratio
Moreover, the coefficient will depend on the specific situation:
- Charging the batteries lasts about 4-20 hours. If the battery charging time is less than 4 hours, the charger should automatically stop working. The current decreases to zero. Next, you can remove the battery, start its operation. If charging takes more than 20 hours, then the battery will not harm the battery.
- The battery capacity is indicated on the battery case. The units of measure are mA / h, A / h (milliampere-hours, ampere-hours).
- The instructions must indicate the charging current. It is either displayed on the display of the charger, or is set in manual mode.
Calculation example
How to determine the battery charging time 60 A? How many minutes will it take to fully restore the battery? To answer this question, you need to know the following parameters: capacitance, current, average coefficient. For example, the capacity is a 1000 mAh battery, the charger current is 150 mAh, and the coefficient is 1.4. Determine the charging time:
(1000/150) * 1.4 = 9.3 hours (9 hours 15-20 minutes)
This indicator is an average. Charging speed varies with:
- temperature
- initial charge;
- chemical composition of the battery.
Battery Maintenance Rules
The main purpose of the battery in a vehicle is to start a car engine. In addition, the battery becomes an emergency power source if the generator fails. There are requirements for the operation and maintenance of batteries that every machine owner should know.
It is recommended not to remove the battery from vehicles with the engine turned on. This in some cases can damage the integrity of the generator. Before removing the battery, in parallel with it, you need to turn on the 12 V incandescent lamp. In this case, the circuit will not open and the generator will not work on itself. Most of the batteries that are currently produced are acid-lead; they use the double sulfation option.
A similar technology has existed since 1858, it is used in its original form today. True, in recent years, batteries for automobiles with an immobilized electrolyte have been produced to a greater extent. They are able to work in all spatial positions. The battery consists of a container in which there are six separate sections. In each section there is an independent generation of energy, and since there are plates, the process of electrolysis. The mass of the battery is 16-17 kilograms, it includes: electrolyte, lead plates, as well as additional compounds.
How does the battery work? The principle of its work is very simple. There is dark brown lead oxide on the anode. At the cathode there is gray spongy lead, inside there is a solution of sulfuric acid (electrolyte). During the chemical reaction, the formation of zinc sulfate, the release of energy. In order to service the battery, no special actions need to be taken.
There are four main battery options, namely:
- served;
- maintenance free;
- Hybrid
- low maintenance.
Let's talk about all the varieties in a little more detail, since they are all used to some extent in everyday life and in technology.
- Served batteries are produced in small quantities, more often they are found in highly specialized industries. They have a high cost, unstable to temperature extremes. That is, at low temperatures, they can spontaneously discharge.
- Low-maintenance batteries are widespread, their price varies in a wide range, they are reliable and durable.
- Maintenance-free batteries are suitable for those who do not want to spend effort on battery care.
- Hybrid batteries are expensive, rare. Charging batteries is best left to professionals.
In order for the battery charging process to be safe, it is advisable to conduct such events outside the living room. The fact is that during charging, hydrogen vapors are released, which can ignite. Therefore, it is strictly forbidden to charge the battery near open sources of fire.