Constant current charging of electric vehicle charger constant current charging means that the battery is charged with piecewise constant current charging method, and the current is adjusted by charging device to achieve. Its main feature is that the charging method has greater adaptability, and the charging current can be arbitrarily selected and adjusted. So it can be for different condition and battery state of charge (such as battery charging, battery charging at the beginning of the used and went charging). The utility model is especially suitable for charging small batteries with long current and long time, charging batteries in series connected by most batteries, and charging the batteries with slower recovery capacity.

However, due to the charging method of charging current is too small to stage, late in the charge and the charge current is too large, so the charging time is long, the precipitation of gas, in plate impact, high energy consumption and low efficiency (less than 65%), and the whole charging process must be supervised. So, at present only the battery initial charge and long time need to use small current charging for desulphurization.

The constant current charging method should pay attention to the following items:

Because the variant of constant current charging is piecewise constant current charging, the charging current should be adjusted in time in order to avoid charging too late. Moreover, the charging current must be strictly enforced, such as the size of the charging current, the charging time, the timing of the switching current and the selection of the charging termination voltage;

The residual capacity of storage battery should be close, otherwise the charging current according to series battery residual capacity minimum selected, and when the battery sufficient should be immediately removed, and then continue to charge for large capacity battery;

The charging process, every 2 ~ 3H to detect a battery cell voltage, if the voltage has reached 2.4V should be promptly transferred to the second stage charging;

When the electrolyte temperature rises to 40 degrees, the charging current should be halved. If it continues to rise to 45 degrees Celsius, the charging current should be stopped and the charge can be continued until the temperature is below 40 degrees celsius;

The battery electrolyte density charge should conform to the requirements, and the electrolyte between the cell density difference should not exceed 0.01g/cm3;

With this method, the maintenance free batteries should not be charged.

(2) electric vehicle charger - constant voltage charging, constant voltage charging refers to each single battery with a constant voltage (usually from cell number * 2.5V) charge. The main features are: the initial charge current is quite large, battery electric potential and the electrolyte density increased rapidly, with the continuation of the charging charging current decreases, the final charge in only a very small current; short charging time, low energy consumption, generally 4 ~ 5h after charging the battery itself can obtain the capacity of 90% ~ 95%; if the charging voltage is chosen appropriately, 8h can complete the whole process of charging, and the charging process without care, it is widely used in charging.

There is a lack of constant charge: the initial charging current is too large, excessive depth of discharge of battery charging, the charging current will cause the early rapid rise, easily caused by overcurrent and charge the battery charging equipment damage; the charging process, because it can not adjust the charging current, it is not suitable for battery charging at the beginning and went charging; charging process due to change of the battery voltage compensation is difficult to fully charge the battery capacity, so it is difficult to complete the slow recovery.

Pay attention to the following items when adopting constant voltage charging method:

Select the charging voltage correctly. If the charging voltage is too high, it will cause excessive charging current in the early stage of charging, and cause serious bending of the plate, large amount of active substances and excessive temperature rise of the battery when it is seriously charged. Too low will lead to insufficient battery charging, resulting in capacity reduction and shortened life;

The terminal voltage of the charged battery must be exactly the same.

(3) electric vehicle charger equalization charging for batteries composed of many single cells, such as fixed battery, after running a certain date, regular equalization charging is necessary. This is because at ordinary times according to the same conditions for charging, the polar parts of the active substances appear different degree of charge phenomenon, the result of active substances appear uneven reaction state. In addition, considering that there are differences in charge and discharge characteristics between individual batteries, some single cell batteries will generate a state of insufficient charge. Therefore, after the end of the normal charging, continue to charge about 20h of current to charge 1 ~ 3h. This charge is also called overcharge. When the battery is used under the same conditions at ordinary times, it is good to do regular charge equalization on battery maintenance.

There are different regulations for each user in the time interval of equalization charging, and some require three months or six months. In recent years, according to the progress of battery design and manufacturing technology, the characteristics of the battery are not very different, so the interval time of the equalization charge is prolonged.

Electric vehicle battery charger (4) - intermittent use of floating charge or use them only in AC power outages when the battery, the charging for float type. For example, for fixed type batteries, each individual cell is charged with a voltage of 2.15 to 2.2V and is charged with continuous small currents. In parallel with the battery charger, the charging current is added to the self discharge loss is about 10h, the rate of 0.3% to 1%, while the usual load of a charger for burden, short time and high load is powered by the battery. The charge is automatically charged because the terminal voltage of the battery drops.

(5) electric vehicle charger constant voltage current limiting constant voltage current limiting charging is mainly used to remedy the disadvantage that the charging current is too large when the constant voltage charge is applied