The charging methods for new energy vehicles (NEVs) are mainly divided into AC charging (Alternating Current) and DC charging (Direct Current). The key differences between AC and DC charging guns lie in charging method, charging speed, equipment structure, and application scenarios.
Below are the detailed distinctions:

1. Different Appearance and Standards

The structure and standards of the two charging guns are different:

• AC (Alternating Current) charging gun:
  The national standard AC gun head has 7 pins, usually including L and N (AC power lines), PE (protective earth), CC (charging confirmation), etc. The AC charging pile is generally smaller in size.

• DC (Direct Current) charging gun:
  The national standard DC gun head has 9 pins, including PE (protective earth), DC+ and DC- (positive and negative poles of DC power), CC1, CC2 (charging confirmation), and more. DC charging piles are much larger, since they contain multiple AC-DC power conversion modules—the higher the power, the more modules, and thus the larger the charging station.

(Note: Standards may vary across different countries.)

2. Difference in Charging Method

• AC Charging:
  AC power is directly delivered to the vehicle, where the onboard charger converts it into DC power before charging the battery. The charging speed is limited by the onboard charger’s power capacity.

• DC Charging:
  The conversion from AC to DC is performed inside the charging station, and DC power is directly fed into the battery, bypassing the onboard charger. This allows higher efficiency and faster charging speed.

3. Difference in Charging Speed

• AC Charging Gun (Slow Charging):
  Commonly used for home or public slow charging, with power ratings ranging from a few kilowatts up to 22 kW.
  It may take several hours to over ten hours for a full charge.

• DC Charging Gun (Fast Charging):
  Typically used at fast-charging stations, with power outputs ranging from tens to hundreds of kilowatts.
  It can charge a vehicle up to 80% or more within tens of minutes, hence called fast charging.

4. Difference in Equipment Structure and Impact on Battery Health

• AC Charging Gun:
  The structure is relatively simple, as the complex energy conversion is handled by the vehicle’s onboard charger.
  During the final stage of charging, the battery pack undergoes cell balancing, ensuring all cells reach full charge evenly.
  This gentle charging process helps extend battery life.

• DC Charging Gun:
  The structure is more complex because the charging station handles the energy conversion and includes more safety protection mechanisms.
  Fast charging requires high-quality batteries, as the high current causes strong electrochemical reactions that deviate from equilibrium.
  Long-term frequent fast charging can shorten battery lifespan and reduce safety margins.
  Additionally, fast charging may lead to false full-charge readings (virtual capacity), meaning the actual range might not match the rated one.

5. Difference in Application Scenarios

• AC Charging Guns are more suitable for home or workplace parking, where the vehicle can remain connected for extended periods.

• DC Charging Guns are ideal for highways, city fast-charging stations, and other situations requiring rapid battery replenishment.

Understanding these distinctions helps users choose the most suitable charging method based on their vehicle type, environment, and usage needs.