AC vs DC power

AC vs DC current

AC stands for “Alternating Current”, and as its name implies, it changes direction periodically. DC stands for “Direct Current” and flows in a straight line. Without getting too technical, AC can be transported over long distances more efficiently, so this is why it flows out of your socket at your home and office. However, batteries are only able to store DC power, and electronics use DC to operate.

You may have never realized it, but every time you charge your phone (or any other electrical device for that matter), the charger converts the AC power it receives from the grid into DC power to charge the battery in your device.

How do electric cars charge?

The same principle goes for electric cars. The difference between AC and DC charging all depends on whether there is a conversion process or not. No matter how you charge it though, at the end of the day, the electricity stored in the car’s battery is always DC.

With a DC charger, power is converted from AC to DC by the charger, allowing direct current to flow straight into the battery. With an AC charger, the electricity has to be converted to DC by the car’s built-in converter before it can be fed into the battery. This process will always take longer as the onboard charger has a much more limited capacity than the external converters used in DC charging stations.