1, fast charge usually refers to DC charging, the DC charging voltage is generally greater than the battery voltage, such as the nominal voltage of the mobile phone battery is generally 3.7V, the charging voltage directly to the mobile phone battery is generally 4.2V. For example, if the battery voltage of an electric vehicle is more than 400 V DC, then the DC charging voltage should be more than 500V, and the current can generally be charged at 1C according to the performance of the power battery, and its electricity is 13KWH, then its charging current should be able to do 32.5A. That is, the power of fast charging is about P=UI=500V*32.5A=16.25KW;
2, slow charge generally refers to the 220V AC socket plugged into the family to charge, because the battery can not accept AC charging. Therefore, it first converts 220V AC to DC and then boosts the charging voltage of the battery, such as 500V DC, and then charges the battery with the 500V DC.
Since the general household 220V AC socket is 10A and 16A, for safety reasons, the charging current of slow charge is generally less than 10A, according to the standard calculation of 10A, the maximum charging power of slow charge is about P=UI=220V*10A=2.2KW. Since 16.25KW is much larger than 2.2KW, we can find that fast charging is much, much faster than slow charging.
The main difference between fast charging and slow charging of new energy vehicles is that the charging speed is different and the charging pile interface is different. Generally speaking, slow charging of new energy vehicles takes 8-10 hours to fully charge the battery, and fast charging only takes 1 hour to charge the battery to 80% of the electricity.
In general, driving outside, you can use fast charge, more convenient and fast. When we go shopping or eat, it only takes 1-2 hours to recharge the car battery. When you get home from work that night, you can use a slow charge, and unplug the charger when you go to work the next day.
Of course, the use of fast charging and slow charging each has advantages and disadvantages, the following detailed analysis.
The advantage of using fast charge is fast and time-saving. However, the fast charge is direct current, the requirements for the battery are not the same, the power of direct current is relatively large, and the life of the battery will be affected for a long time.
The advantage of using slow charge is that it will not cause any damage to the battery, and the charge is true, relatively easy to use, but the charging speed is relatively slow, sometimes causing unnecessary trouble.
When purchasing new energy vehicles, ask the 4s shop in advance whether it provides the service of installing charging piles. And when installing the charging pile, it is also necessary to inform the property in advance to avoid unnecessary trouble.