Car Battery Charger Calculator Calculator
Charging requires not only the fully-sitting battery (it is not desirable to bring it), but also the battery is in operation. But time of recharge Will they have different. Often that from 8 to 12 hours. Our online calculator will help calculate how much you need to charge a car batteryUsing constant current for this.
The first charge of a new (uncharged) battery may continue relative to long: 25-50 hours (depends on the state of the AKB). How long will be charged with a used battery depends on its degree of discharge, operating time and condition. For a highly discharged battery, you may need 14-16 hours or more.
When, how and how to charge
As a rule, the degree of charge of the battery is judged by the density of its electrolyte. The density of the fully charged battery should be 1.26-1.28 g / cm³, voltage of at least 12.5 V. Everything will depend on whether it was initially installed in the new battery of your region of living, maybe as 12.7 in the so 12 , 9B. The density is lower, the stronger it is discharged. A decrease in density by 0.01 g / cm3 compared to the nominal means that the battery was discharged by about 6-8%. The degree of charge must be determined by the bank having the smallest density.
| Degree of charge (%) | Electrolyte density (g / cm³) | Degree of discharge (%) | Rechargeable Battery Voltage (B) | Charge time at 10% of the tank (clock) |
|---|---|---|---|---|
| 100 | 1,277 | 0 | 12,73 | Not necessary |
| 90 | 1,258 | 10 | 12,62 | 2 |
| 80 | 1,238 | 20 | 12,50 | 4 |
| 70 | 1,217 | 30 | 12,37 | 6 |
| 60 | 1,195 | 40 | 12,24 | 8 |
| 50 | 1,172 | 50 | 12,10 | 10 |
| 40 | 1,148 | 60 | 11,96 | 13 |
| 30 | 1,124 | 70 | 11,81 | 16 |
| 20 | 1,098 | 80 | 11,66 | 20 |
| 10 | 1,073 | 90 | 11,51 | 24 |
| 0 | 1,06 | 100 | 11,4 | Sulfation |
The lead-acid battery, which is discharged in summer by more than 50%, and even in winter, even more than 25% must be removed and recharged. Also additional charging requires that battery, the density in the banks of which is different by more than 0.02 g / cm³.
The optimal current of the battery charging is considered current equal to 0.05 from its tank ( equal charge). So for the battery with a capacity of 55 AM / h, this value is 2.75 A, and for 60 Ah already 3 amps. The purpose of this method is to ensure the complete restoration of the active masses in all the plates of the battery.
The equalizing charge is able to neutralize the impact of deep discharges. Recommended when eliminating the sulfation of electrodes caused by long-term operation of the AKB during charges of less than 70%.
Although often use the so-called forced charge and take another ratio - 10% of the tank. That is the standard car battery 55Ah Charge 2.75-5.5A, and for 60Ah battery Charging current exhibit within from 3a to 6a. But, you need to know that the smaller the charging current, the deeper charge, although it takes more time. Exactly the same situation and applied voltage - the greater the fasterBut, it should not fall below 13.8 and exceed 14.5V.). Charging voltage raise until 16.0-16,5V. only when charging a non-servant battery.
Serve the current above 1/10 of its capacity is harmful, but below 1/20 will be useless when charging.
It should be noted that today there are several methods for recharging AKB:
- At constant current;
- At constant voltage;
- Combination in automatic mode (we will not consider it, since in this case the counting calculator is not needed).
Car battery discharge stages
Charging time AKB with constant current
The formula for calculating the charging current has the form: I \u003d Q * k, where q is the battery capacity, and k is a certain ratio from the nominal value (the ideal value is in the boundaries of 0.04 ... 0.06, and optimal up to 0.1). Based on such a recommendation, counting the time, which is necessary for a fully planted battery, has this kind: T \u003d Q / I. Substitting your values, you will see that it turns out quite a lot of time, but since it is often necessary not to complete charging, but only the recovery is lost Capacities, then this figure will be two or one and a half times less.
For approximate estimate of the required time for charging a car battery dC First, it is necessary to determine the degree of blockage of the battery (as a percentage), then define the lost container (in the ACH), and then by selecting the charging current value, calculate the time of complete charge. The formula for calculating how much time to recharge the battery auto looks like this:
The multiplication of this ratio is 2 times, due to the fact that the efficiency of the process is 40-50%, the rest is spent on heating, as well as the associated electrochemical processes.
The use of the calculated formula must necessarily be accompanied by controlling the progress of the charging process, especially when it is completed, in order not to miss the beginning of the stormy boiling.
When within an hour on the battery terminals, when charging, the voltage ceases to increase - the battery is 100% charged.
The magnitude of the final voltage depends on: the values \u200b\u200bof the charging current, the temperature, the internal resistance of the battery, the presence of impurities in the electrolyte and the composition of the lattice alloy.
How to use the calculator
To find out how much time you need to charge your battery, you do not need to go into the details of all processes and the calculated formulas, it is enough to use this calculator.
For online calculation you need to fill all three fields:
- In the "Nominal Capacity" field fits the capacity of the charged auto accumulator.
- In the "Degree of Discharge" field, you can enter both the percentage ratio calculated on the table and the voltage measured by a voltmeter.
- In the charging current cell, you need to specify anyway, you plan to charge the battery from the charger.
