According to the charging method, charging piles can be divided into AC charging piles, DC charging piles, and AC/DC integrated charging piles. Among them, AC charging has low power and requires a long charging time, but the loss to the battery is small. In contrast, DC charging piles have high charging power and fast charging, but the loss to the battery is also large.

(1) AC charging piles:

AC electric vehicle charging piles, commonly known as "slow charging", are fixedly installed outside the electric vehicle and connected to the AC power grid. They provide AC power to the on-board charger of the electric vehicle (i.e., the charger fixedly installed on the electric vehicle). AC charging piles only provide power output and have no charging function. They need to be connected to the on-board charger to charge the electric vehicle. It is equivalent to just playing the role of controlling the power supply.

Currently, charging piles are divided into AC charging piles and DC charging piles. AC piles output single-phase/three-phase AC power, which is converted into DC power by the on-board charger to charge the on-board battery. The power is generally small (7kw, 22kw, 40kw, etc.), and the charging speed is generally slow, so they are generally installed in community parking lots and other places.

(2) DC charging pile:

DC electric vehicle charging station, commonly known as "fast charging", is a power supply device fixedly installed outside the electric vehicle and connected to the AC power grid. It can provide DC power for the off-board electric vehicle power battery. The input voltage of the DC charging pile adopts three-phase four-wire AC 380 V±15%, frequency 50Hz, and the output is adjustable DC power, which directly charges the power battery of the electric vehicle. Since the DC charging pile adopts three-phase four-wire power supply, it can provide sufficient power, and the output voltage and current adjustment range is large, which can meet the requirements of fast charging.

DC charging piles (or off-board chargers) directly output DC power to charge the on-board battery. They have large power (60kw, 120kw, 200kw or even higher) and fast charging speed, so they are generally installed at charging stations beside highways.