The proper charging method of 12V battery

1. Constant current charging. The popular understanding is that the current during charging is also called the flow filling method. When charging, the battery power supply continues to rise and the current continues to decrease. In order to keep the current constant, only the charging voltage can be increased. This situation of charging equipment is highly automated, and ordinary charging equipment cannot meet the requirements. The charging method can greatly shorten the charging time, but the high voltage in the back is likely to cause the battery temperature to rise and be scrapped in advance.

2. Constant voltage charging. This method is referred to as isobaric charging. Since the power supply remains unchanged, the internal voltage of the battery is continuously increased and the current is gradually reduced. The advantage of this method is to avoid loss of electrical energy and loss of active material in the battery. The disadvantage is that the charging current is large, the active material shrinkage block is easy to fall off, and the current is reduced in the late charging period, and the active material is insufficiently charged to obtain an effective reaction, thereby reducing the battery life.

3. Fixed resistor charging. Constant resistance charging is to connect a resistor between the power supply and the battery. At this time, the charging current can be adjusted, but as the charging continues, the power supply gradually rises, the resistance does not change, the current is extremely reduced, and even the power is always generated, but the phenomenon cannot be filled.

1: Pulse charging, a simple and economical method is that the low-voltage AC rectification of the secondary output of the transformer is pulsating DC (no filtering) to charge the battery. This method has a large charging current and a fast charging speed. The disadvantage is that when the grid voltage fluctuates, the charging current also fluctuates. It is easy to occur because the charging current is large, the battery temperature is increased, and the electrolyte loss is large, resulting in battery damage. Therefore, this method is rarely used for maintenance-free sealed lead-acid batteries.

2. With constant current charging, in order to prevent the temperature rise in the battery from being too high and the loss of the electrolyte is too large, the charging current is adjusted to be relatively small, and the charging time is required to be long. On the other hand, if the charging time is too long, overcharging may occur. In order to prevent damage to the battery due to overcharging, an overcharge detection or timing circuit is required.

3. Constant voltage charging, both theory and practice, proves that when the charging voltage is lower than the upper limit of the charging voltage (this value is for 12V batteries), constant voltage charging is safe, even if the charging time is long, there is no danger, if necessary, The battery can also work in a floating state.

Constant current charging method; Constant voltage charging method; Stage charging method.

1. Constant current charging method

It is a charging method that adjusts the output voltage of the charging device or changes the resistance in series with the battery to keep the charging current intensity constant. The control method is simple.

2. Constant voltage charging method

The voltage of the charging power source maintains a constant value during the entire charging time, and the current gradually decreases as the voltage of the battery terminal gradually increases. Compared with the constant current charging method, the charging process is closer to the optimal charging curve. However, in the initial stage of charging, the current is too large, which has a great influence on the battery life, and it is easy to bend the battery plate and cause the battery to be scrapped.

3. Stage charging method

This method includes a two-stage charging method and a three-stage charging method.

The two-stage method employs a fast charging method in which a constant current and a constant voltage are combined. First, charging with a constant current to a predetermined voltage value, and then changing to a constant voltage to complete the remaining charging.

The two-stage charging method uses constant current charging at the beginning and end of charging, and is charged with a constant voltage in the middle. When the current decays to a predetermined value, the second phase is switched to the third phase.

12V battery charging operation procedures

1. Preparation before charging:

1.1. Starting battery sometimes due to large discharge of battery or long-term storage, the battery is depleted, so it should be set regularly.

The battery is removed and the battery is recharged in the charging room. Recharge is usually done once a month to improve its reliability and extend its service life. It is best to make a supplementary charge when entering the winter.

1.2. Before charging, measure the voltage of the battery with a universal meter and record it, so as to determine according to the loss of each battery.

Charging  solution.

1.3. Check whether the AC power supply meets the requirements for use. The power supply should be 220V, 50Hz AC.

1.4. Connect the battery first, connect the "+" pole of the charger to the "+" pole of the battery, and the "-" pole of the charger to the battery "-"

On the poles, take care to prevent short-circuiting of the load. 1.5. Select the charging voltage. If the rechargeable battery is 12V, the voltage selection file should be rotated to 12V, if the rechargeable battery is 24V,

Then the voltage selection file should be rotated to 24V, and the error should not be selected, otherwise the charger or battery will be damaged. 2. Charging operation:

2.1. Initial charging and supplementary charging are often performed by constant current charging (constant current charging is always constant for a certain period of time)

The variable current charges the battery, which has the advantage that the charging is relatively complete, but the late current is almost completely consumed in the decomposition of water and the occurrence of heat. The charging current is 0.1C20A (such as 6A for 60Ah battery), the charging time is 3~5h, or the charging time is determined according to the length of storage time. 2.2. Maintenance charging often uses constant voltage charging (constant voltage charging is always charging the battery with a constant voltage.

The advantage is that gas generation is small, water consumption is small, and there is a disadvantage that charging is incomplete. The cell voltage is usually set at 2.3 to 2.4V (13.8 to 14.4V for a 12V battery and 6.9 to 7.2V for a 6V battery) until fully charged). 2.3. Adjust the charger current selection gear to the lowest gear.

2.4. Ensure that the red and black clips are not in contact before they can be energized, otherwise it will cause a short circuit and damage the machine; 2.5. Charging uses a two-step charging method:

2.5.1. That is, the first step is to charge from 0.1C20A to 12V battery is 13.8~14.4V, and the 6V battery is 6.9~7.2V.

Transfer to the second step of charging, the second step of charging using 0.05C20A to the end of charging.

2.5.2. Turn on the 220V power supply and adjust the charging current step by step to the maximum charging current of 0.1C20A for the first step of charging.

Namely: for 12V, the 54Ah battery has a charging current of 0.1x54=5.4A.

For 12V, 150Ah battery has a charging current of 0.1x150=15A

2.5.3. When the battery voltage reaches 13.8~14.4V, it will be transferred to the second step of charging. The maximum current of the second step is 0.05C20A.

That is, for 12V, the charging current of the 54Ah battery is 0.0511x54=2.7A, and for the 12V, the charging current of the 150Ah battery is 0.05x150=7.5A.

2.5.4. After the battery is fully charged, the battery is finally balanced and charged to ensure the cell balance. The method is: fully charged

The battery is charged with 0.035C20A current (12V, 54Ah battery charging current is 0.035x54=1.89A; 12V, 150Ah battery charging current is 0.035x150=5.25A); when the battery emits uniform bubbles, the temperature rises, stop charging 1 Hours; this is repeated 3 to 4 times, the cells can emit uniform bubbles, and the battery voltage and electro-hydraulic density tend to be constant.

2.6. Determination of charging time:

Recharge time and battery voltage correspondence (reference): battery voltage replenishment time 12.55-12.45V 2hours 12.45-12.35V 3hours 12.35-12.20V 4hours 12.20-12.05V 5hours 12.05-11.95V 6hours

11.95-11.80V 7hours 11.80-11.65V 8hours 11.65-11.50V 9hours 11.50-11.30V 10hours 11.30-11.00V 12hours 11.00V below 14 hours

2.7. After charging is completed, check the color of the battery electric eye (maintenance-free battery, the same below). The electric eye is displayed in green, indicating

The battery is fully charged. If the electric eye is black, check if the charging cable is securely connected, whether the connection point is clean, whether the charging voltage reaches 16 volts, and continue to recharge.

The page contains the contents of the machine translation.